1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
1
General Properties
Name Hydrogen
Symbol H
Atomic Number 1
Pronunciation /ˈhaɪdrɵdʒɨn/hye-dro-jin
Element category nonmetal
Group 1
Period 1
Block s
Atomic Weight 1.00794(7)
Electron configuration 1s1
Electrons per shell 1
Atomic Properties
Oxidation states 1, -1 (amphoteric oxide)
Electronegativity 2.20 (Pauling scale)
Ionization energies 2.20 (Pauling scale)
Covalent radius 31±5 pm
Van der Waals radius 120 pm
Miscellanea
Crystal structure hexagonal
Magnetic ordering diamagnetic
Thermal conductivity 0.1805 W·m−1·K−1
Speed of sound (gas, 27 °C) 1310 m·s
CAS registry number 1333-74-0
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K)         15 20
Physical Properties
Color colourless
Phase gas
Density (0 °C, 101.325 kPa)0.08988 g/L
Liquid Density at m.p. 0.07 (0.0763 solid) g·cm−3
Liquid density at b.p. 0.07099 g·cm−3
Melting Point 14.01 K,-259.14 °C,-434.45 °F
Boiling Point 20.28 K,-252.87 °C,-423.17 °F
Triple Point 13.8033 K (-259°C), 7.042 kPa
Critical point 32.97 K, 1.293 MPa
Heat of Fusion (H2) 0.117 kJ·mol−1
Heat of Vaporization (H2) 0.904 kJ·mol−1-1
Molar heat capacity (H2) 28.836 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
1H 99.985% 1H is stable with 0 neutrons
2H 0.015% 2H is stable with 0 neutrons
3H trace 12.32 y β− 0.01861 3He
 
H
Other Metals Post-Transition Metals Metalloids
General properties
Name Helium
Symbol He
Atomic Number 2
Pronunciation /ˈhiːliəm/ hee-lee-əm
Element category noble gases
Group 18
Period 1
Block s
Atomic Weight 4.002652(2)
Electron configuration 1s2
Electrons per shell 2
Atomic Properties
Oxidation states  
Electronegativity no data (Pauling scale)
Ionization energies 1st: 2372.3 kJ·mol−1 2nd: 5250.5 kJ·mol−1
Covalent radius 28pm
Van der Waals radius 135pm
Miscellanea
Crystal structure hexagonal close-packed
Magnetic ordering diamagnetic
Thermal conductivity 0.1513 W·m−1·K−1
Speed of sound 972 m·s−1
CAS registry number 7435-59-7
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K)     1.23 1.67 2.48 4.21
Physical Properties
Color  
Phase gas
Density (0 °C, 101.325 kPa) 0.1786 g/L
Liquid Density at m.p. 0.145 g·cm−3
Liquid density at b.p.  
Melting Point (at 2.5 MPa) 0.95 K,−272.20 °C,−457.96 °F
Boiling Point 4.22 K,−268.93 °C,−452.07 °F
Triple Point  
Critical point 5.19 K, 0.227 MPa
Heat of Fusion 0.0138 kJ·mol−1
Heat of Vaporization 0.0829 kJ·mol−1
Molar heat capacity 5R/2 = 20.786 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
3He 0.000137%* 3He is stable with 1 neutron
4He 99.999863%* 4He is stable with 2 neutron
*Atmospheric value, abundance may differ elsewhere.
He
2
General Properties
Name Lithium
Symbol Li
Atomic Number 3
Pronunciation /ˈlɪθiəm/ li-thee-əm
Element Category alkali metal
Group 1
Period 2
Block s
Atomic Weight 6.941(2)
Electron Configuration 1s2 2s1 or [He]2s1
Electrons Per Shell 2, 1
Atomic Properties
Oxidation States +1, -1 (strongly basic oxide)
Electronegativity 0.98 (Pauling scale)
Ionization Energies 1st: 520.2 kJ·mol−1
2nd: 7298.1 kJ·mol−1
3rd: 11815.0 kJ·mol−1
Atomic radius 152 pm
Covalent Radius 128±7 pm
Van der Waals Radius 182 pm
Miscellanea
Crystal Structure body-centered cubic
Magnetic Ordering paramagnetic
Electrical resistivity (20 °C) 92.8 nΩ·m
Thermal Conductivity 84.8 W·m−1·K−1
Thermal Expansion (25 °C) 46 µm·m−1·K−1
Speed of Sound (20 °C) 6000 m·s
Young's modulus 4.9 GPa
Shear modulus 4.2 GPa
Bulk modulus 11 GPa
Mohs hardness 0.6
CAS Registry Number 7439-93-2
Physical Properties
Phase solid
Density 0.534 g·cm−3
Liquid Density at m.p. 0.512 g·cm−3
Melting Point 453.69 K,180.54 °C,356.97 °F
Boiling Point 1615 K,1342 °C,2448 °F
Critical Point (extrapolated) 3223 K, 67 MPa
Heat of Fusion 3.00 kJ·mol−1
Heat of Vaporization 147.1 kJ·mol−1
Molar Heat Capacity 24.860 J·mol·K
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 797 885 995 1144 1337 1610
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
6Li 7.5% 6Li is stable with 3 neutrons
7Li 92.5% 7Li is stable with 3 neutrons
6Li content may be as low as 3.75% in
natural samples. 7Li would therefore
have a content of up to 96.25%.
Li
General properties
Name Beryllium
Symbol Be
Atomic Number 4
Pronunciation /bəˈrɪliəm/ bə-ril-ee-əm
Element category Alkaline Earth Metal
Group 2
Period 2
Block s
Atomic Weight 9.012182(3)
Electron configuration 1s2 2s2
Electrons per shell 2, 2
Atomic Properties
Oxidation states 2, 1(amphoteric oxide)
Electronegativity 1.57 (Pauling scale)
Ionization energies 1st: 899.5 kJ·mol−1 2nd: 1757.1 kJ·mol−1 3rd: 14848.7 kJ·mol−1
Atomic radius 112 pm
Covalent radius 96±3 pm
Van der Waals radius 153 pm
Miscellanea
Crystal structure hexagonal
Magnetic ordering diamagnetic
Electrical resistivity (20 °C) 36 nΩ·m
Thermal conductivity 200 W·m−1·K−1
Thermal expansion 200 W·m−1·K−1
Speed of sound(thin rod) (r.t.) 12870 m·s
Young's modulus 287 GPa
Shear modulus 132 GPa
Bulk modulus 130 GPa
Poisson ratio 0.032
Mohs hardness 5.5
Vickers hardness 1670 MPa
Brinell hardness 600 MPa
CAS registry number 7440-41-7
Physical Properties
Color  
Phase solid
Density 1.85 g·cm−3
Liquid Density at m.p. 1.690 g·cm−3
Liquid density at b.p.  
Melting Point 1560 K,1287 °C,2349 °F
Boiling Point 2742 K,2469 °C,4476 °F
Triple Point  
Critical point  
Heat of Fusion 12.2 kJ·mol−1
Heat of Vaporization 297 kJ·mol−1
Molar heat capacity 16.443 J·mol·K
Most Stable Isotopes
Main article: Isotopes of hydrogen
iso NA half-life DM DE (MeV) DP
7Be trace 53.12 d ε 0.862 7Li
γ 0.477  
8Be trace 7*10-17s α   4He
9Be 100% 9Be is stable with 5 neutrons
10Be trace 1.36*106 y β− 0.556 10B
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1462 1608 1791 2023 2327 2742
Be
Alkali Metals Other Non Metals Noble Gases
General Properties
Name Boron
Symbol B
Atomic Number 5
Pronunciation /ˈbɔrɒn/
Element Category metalloid
Group 13
Period 2
Block p
Atomic Weight 10.811(7)
Electron Configuration [He] 2s2 2p1
Electrons Per Shell 2, 3
Atomic Properties
Oxidation States 3, 2, 1 (mildly acidic oxide)
Electronegativity 2.04 (Pauling scale)
Ionization energies 1st: 800.6 kJ·mol−1
2nd: 2427.1 kJ·mol−1
3rd: 3659.7 kJ·mol−1
Atomic radius 90 pm
Covalent Radius 84±3 pm
Van der Waals Radius 192 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 2348 2562 2822 3141 3545 4072
Physical Properties
Phase solid
Liquid Density at m.p. 2.08 g·cm−3
Melting Point 2349 K,2076 °C,3769 °F
Boiling Point 4200 K,3927 °C,7101 °F
Heat of Fusion 50.2 kJ·mol−1
Heat of Vaporization 480 kJ·mol−1
Molar Heat Capacity 11.087 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
10B 19.9(7)%* 10B is stable with 5 neutrons
11B 80.1(7)%* 11B is stable with 6 neutrons
*Boron-10 content may be as low as 19.1% and as
high as 20.3% in natural samples. Boron-11 is
the remainder in such cases.
Miscellanea
Magnetic Ordering diamagnetic
Electrical Resistivity (20 °C) ~106 Ω·m
Thermal Conductivity 27.4 W·m−1·K−1
Thermal Expansion (25 °C) (ß form) 5–7 µm·m−1·K−1
Speed of Sound (20 °C) 16,200 m·s
Mohs hardness ~9.5
CAS Registry Number 7440-42-8
B
General Properties
Name Carbon
Symbol C
Atomic Number 6
Pronunciation /ˈkɑrbən/
Element Category nonmetal
Group 14
Period 2
Block p
Atomic Weight 12.0107(8)
Electron Configuration 1s2 2s2 2p2 or [He] 2s2 2p2
Electrons Per Shell 2,4
Atomic Properties
Oxidation States 4, 3, 2, 1, 0, -1, -2, -3, -4[6]
Electronegativity 2.55 (Pauling scale)
Ionization energies 1st: 800.6 kJ·mol−1
2nd: 2352.6 kJ·mol−1
3rd: 4620.5 kJ·mol−1
Covalent Radius 77(sp3), 73(sp2), 69(sp) pm
Van der Waals Radius 170 pm
Miscellanea
Magnetic Ordering diamagnetic[7]
Thermal Conductivity 119-165 (graphite) 900-2300 (diamond) W·m−1·K−1
Thermal expansion (25 °C) 0.8 (diamond) [8] µm·m-1·K
Speed of Sound (20 °C) 18350 (diamond) m·s
Young's modulus 1050 (diamond)[8] GPa
Shear modulus 478 (diamond) [8] GPa
Bulk modulus 442 (diamond)[8] GPa
Poisson ratio 0.1 (diamond) [8]
Mohs hardness 1-2 (Graphite) 10 (Diamond)
CAS Registry Number 7440-44-0
Physical Properties
Phase solid
Density amorphous:1.8–2.1 g·cm−3
Sublimation point 3915 K,3642 °C,6588 °F
Triple Point 4600 K (4327°C), 10800[2][3] kPa
Heat of Fusion 117 (graphite) kJ·mol−1
Molar Heat Capacity 8.517(graphite), 6.155(diamond) J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
11C syn 20 min β+ 0.96 11B
12C 98.9% 12C is stable with 6 neutrons
13C 1.1% 13C is stable with 7 neutrons
14C trace 5730 y β- 0.15 14N
C
General Properties
Name Nitrogen
Symbol N
Atomic Number 7
Pronunciation /ˈnaɪtrɵdʒɨn/ nye-tro-jin
Element Category nonmetal
Group 15
Period 2
Block p
Atomic Weight 14.0067(2)
Electron Configuration 1s2 2s2 2p3
Electrons Per Shell 2, 5
Atomic Properties
Oxidation States 5, 4, 3, 2, 1, -1, -2, -3 (strongly acidic oxide)
Electronegativity 3.04 (Pauling scale)
Ionization energies 1st: 1402.3 kJ·mol−1
2nd: 2856 kJ·mol−1
3rd: 4578.1 kJ·mol−1
Covalent Radius 71±1 pm
Van der Waals Radius 155 pm
Miscellanea
Crystal Structure hexagonal
Magnetic Ordering diamagnetic
Thermal Conductivity 25.83 * 10−3 W·m−1·K−1
Speed of Sound (gas, 27 °C) 353 m·s
CAS Registry Number 7727-37-9
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 37 41 46 53 62 77
Physical Properties
Color
Phase gas
Density (0 °C, 101.325 kPa) 1.251 g/L
Liquid Density at b.p. 0.808 g·cm−3
Melting Point 63.15 K,-210.00 °C,-346.00 °F
Boiling Point 77.36 K,-195.79 °C,-320.33 °F
Triple Point 63.1526 K (-210°C), 12.53 kPa
Critical Point 126.19 K, 3.3978 MPa
Heat of Fusion (N2) 0.72 kJ·mol−1
Heat of Vaporization (N2) 5.56 kJ·mol−1
Molar Heat Capacity (N2) 29.124 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
13N syn 9.965 min ε 2.220 13C
14N 99.634% 14N is stable with 7 neutrons
15N 0.366% 15N is stable with 8 neutrons
N
General Properties
Name Oxygen
Symbol O
Atomic Number 8
Pronunciation /ˈɒksɨdʒɨn/ ok-si-jin
Element Category nonmetal, chalcogen
Group 16
Period 2
Block p
Atomic Weight 15.9994(3)
Electron Configuration 1s2 2s2 2p4
Electrons Per Shell 2, 6
Atomic Properties
Oxidation States 2, 1, -1, −2
Electronegativity 3.44 (Pauling scale)
Ionization energies 1st: 1313.9 kJ·mol−1
2nd: 3388.3 kJ·mol−1
3rd: 5300.5 kJ·mol−1
Covalent Radius 66±2 pm
Van der Waals Radius 152 pm
Miscellanea
Crystal Structure cubic
Magnetic Ordering paramagnetic
Thermal Conductivity 26.58x10−3 W·m−1·K−1
Speed of Sound (gas, 27 °C) 330 m·s
CAS Registry Number 7782-44-7
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 61 73 90
Physical Properties
Phase gas
Density (0 °C, 101.325 kPa) 1.429 g/L
Liquid Density at b.p. 1.141 g·cm−3
Melting Point 54.36 K,-218.79 °C,-361.82 °F
Boiling Point 90.20 K,-182.95 °C,-297.31 °F
Critical Point 154.59 K, 5.043 MPa
Heat of Fusion (O2) 0.444 kJ·mol−1
Heat of Vaporization (O2) 6.82 kJ·mol−1
Molar Heat Capacity (O2) 29.378 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
16O 99.76% 16O is stable with 8 neutrons
17 0.039% 17O is stable with 9 neutrons
18 0.201% 18O is stable with 10 neutrons
O
General Properties
Name Fluorine
Symbol F
Atomic Number 9
Pronunciation /ˈflʊəriːn/, /ˈflʊərɪn/, /ˈflɔːriːn/
Element Category halogen
Group 17
Period 2
Block p
Atomic Weight 18.9984032(5)
Electron Configuration 1s2 2s2 2p5
Electrons Per Shell 2, 7
Atomic Properties
Oxidation States -1 (oxidizes oxygen)
Electronegativity 3.98(Pauling scale)
Ionization Energies 1st: 1681.0 kJ·mol−1
2nd: 3374.2 kJ·mol−1
3rd: 6050.4 kJ·mol−1
Covalent Radius 60 pm
Van der Waals Radius 147 pm
Miscellanea
Crystal Structure cubic
Magnetic Ordering diamagnetic
Thermal Conductivity 0.02591 W·m−1·K−1
CAS Registry Number 7782-41-4
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 38 44 50 58 69 85
Physical Properties
Phase gas
Density (0 °C, 101.325 kPa) 1.696g/L
Liquid Density at b.p. 1.505 g·cm−3
Melting Point 53.53 K,−219.62 °C,−363.32[5] °F
Boiling Point 85.03 K,-188.12 °C,−306.62[5] °F
Critical Point 144.00 K, 5.220[6] MPa
Heat of Fusion 0.51[7]kJ·mol−1
Heat of Vaporization 3.27[7] kJ·mol−1
Molar Heat Capacity (Cp) (21.1 °C) 825[8] J·mol·K (Cv) (21.1 °C) 610[8] J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
18F trace 109.77 min β+ (97%) 0.633 18O
ε (3%) 1.656 18O
19F 100% 19F is stable with 10 neutrons
F
General Properties
Name Neon
Symbol Ne
Atomic Number 10
Pronunciation /ˈniːɒn/
Element Category noble gases
Group 18
Period 2
Block p
Atomic Weight 20.1797(6)
Electron Configuration 1s2 2s2 2p6
Electrons Per Shell 2, 8
Atomic Properties
Oxidation States no data
Ionization Energies 1st: 2080.7 kJ·mol−1
2nd: 3952.3 kJ·mol−1
3rd: 6122 kJ·mol−1
Covalent Radius 58 pm
Van der Waals Radius 154 pm
Miscellanea
Crystal Structure face-centered cubic
Magnetic Ordering diamagnetic
Thermal Conductivity 49.1x10-3 W·m-1·K-1
Speed of Sound (gas, 0 °C) 435 m·s-1
Bulk modulus 654 GPa
CAS Registry Number 7440-01-9
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 12 13 15 18 21 27
Physical Properties
Phase gas
Density (0 °C, 101.325 kPa) 0.9002 g/L
Liquid Density at b.p. 1.207 g·cm−3
Melting Point 24.56 K,-248.59 °C,-415.46 °F
Boiling Point 27.07 K,-246.08 °C,-410.94 °F
Triple Point 24.5561 K (-249°C), 43[2][3] kPa
Critical Point 44.4 K, 2.76 MPa
Heat of Fusion 0.335 kJ·mol−1
Heat of Vaporization 1.71 kJ·mol−1
Molar Heat Capacity 5R/2 = 20.786 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
20Ne 90.48% 20Ne is stable with 10 neutrons
21Ne 0.27% 21Ne is stable with 11 neutrons
22Ne 9.25% 22Ne is stable with 12 neutrons
Ne
3
General Properties
Name Sodium
Symbol Na
Atomic Number 11
Pronunciation /ˈsoʊdiəm/ soh-dee-əm
Element Category alkali metal
Group 1
Period 3
Block s
Atomic Weight 22.98976928(2)
Electron Configuration [Ne] 3s1
Electrons Per Shell 2,8,1
Atomic Properties
Oxidation States +1, 0, -1 (strongly basic oxide)
Electronegativity 0.93 (Pauling scale)
Ionization Energies 1st: 495.8 kJ·mol−1
2nd: 4562 kJ·mol−1
3rd: 6910.3 kJ·mol−1
Atomic radius 186 pm
Covalent Radius 166±9 pm
Van der Waals Radius 227 pm
Miscellanea
Crystal Structure body-centered cubic
Magnetic Ordering paramagnetic
Electrical Resistivity (20 °C) 47.7 nΩ·m
Thermal Conductivity 142 W·m−1·K−1
Thermal Expansion (25 °C) 71 µm·m−1·K−1
Speed of Sound (20 °C) 3200 m·s
Young's Modulus 10 GPa
Shear Modulus 3.3 GPa
Bulk Modulus 6.3 GPa
Mohs Hardness 0.5
Brinell Hardness 0.69 MPa
CAS Registry Number 7440-23-5
Vapour Pressure
P (Pa) 1 10 100 1K 10K 1OOK
at T (K) 554 617 697 802 946 1153
Physical Properties
Phase solid
Density 0.968 g·cm−3
Liquid Density at m.p. 0.927 g·cm−3
Melting Point 370.87 K,97.72 °C,207.9 °F
Boiling Point 1156 K,883 °C,1621 °F
Critical Point (extrapolated) 2573 K, 35 MPa
Heat of Fusion 2.60 kJ·mol−1
Heat of Vaporization 97.42 kJ·mol−1
Molar Heat Capacity 28.230 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
22Na trace 2.602 y β+→γ 0.5454 22Ne*
1.27453(2) 22Ne
ε→γ - 22Ne*
1.27453(2) 22Ne
β+ 1.8200 22Ne
23Na 100% 23Na is stable with 12 neutrons
Na
General Properties
Name Magnesium
Symbol Mg
Atomic Number 12
Pronunciation /mæɡˈniːziəm/, mag-nee-zee-əm
Element Category alkaline earth metal
Group 2
Period 3
Block s
Atomic Weight 24.3050(6)
Electron Configuration [Ne] 3s2
Electrons Per Shell 2, 8, 2
Atomic Properties
Oxidation States 2, 1 (strongly basic oxide)
Electronegativity 1.31 (Pauling scale)
Ionization Energies 1st: 737.7 kJ·mol−1
2nd: 1450.7 kJ·mol−1
3rd: 7732.7 kJ·mol−1
Atomic Radius 160 pm
Covalent Radius 141±7 pm
Van der Waals Radius 173 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 701 773 861 971 1132 1361
Physical Properties
Phase solid
Density 1.738 g·cm−3
Liquid Density at m.p. 1.584 g·cm−3
Melting Point 923 K,650 °C,1202 °F
Boiling Point 1363 K,1091 °C,1994 °F
Heat of Fusion 8.48 kJ·mol−1
Heat of Vaporization 128 kJ·mol−1
Molar Heat Capacity 24.869 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
24Mg 78.99% 24Mg is stable with 12 neutrons
25Mg 10% 25Mg is stable with 13 neutrons
26Mg 11.01% 26Mg is stable with 14 neutrons
Miscellanea
Crystal Structure hexagonal
Magnetic Ordering paramagnetic
Electrical Resistivity (20 °C) 43.9 nΩ·m
Thermal Conductivity 156 W·m−1·K−1
Thermal Expansion (25 °C) 24.8 µm·m−1·K−1
Speed of Sound 4940 m·s
Young's Modulus 45 GPa
Shear Modulus 17 GPa
Bulk Modulus 45 GPa
Poisson Ratio 0.290
Mohs Hardness 2.5
Brinell Hardness 260 MPa
CAS Registry Number 7439-95-4
Mg
Halogens Alkali Earth Metals Lanthanides & Actinides
General Properties
Name Aluminium
Symbol Al
Atomic Number 13
Pronunciation /əˈluːmɨnəm/;ə-loo-mi-nəm
Element Category other metal
Group 13
Period 2
Block p
Atomic Weight 26.9815386(13)
Electron Configuration [Ne] 3s23p1
Electrons Per Shell 2, 8, 3
Atomic Properties
Oxidation States 3, 2, 1 (amphoteric oxide)
Electronegativity 1.61 (Pauling scale)
Ionization Energies 1st: 577.5 kJ·mol−1
2nd: 1816.7 kJ·mol−1
3rd: 2744.8 kJ·mol−1
Atomic Radius 143 pm
Covalent Radius 121±4 pm
Van der Waals Radius 184 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1482 1632 1817 2054 2364 2790
Physical Properties
Phase solid
Density(near r.t.) 2.70 g·cm−3
Liquid Density at m.p. 2.375 g·cm−3
Melting Point 933.47 K,660.32 °C,1220.58 °F
Boiling Point 2792 K,2519 °C,4566 °F
Heat of Fusion 10.71 kJ·mol−1
Heat of Vaporization 294.0 kJ·mol−1
Molar Heat Capacity 24.200 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
26Al trace 7.17*105y β+ 1.17 26Mg
ε - 26Mg
γ 1.8086 -
27Al 100% 27Al is stable with 14 neutrons
Miscellanea
Crystal Structure face-centered cubic
Magnetic Ordering paramagnetic
Electrical Resistivity (20 °C) 28.2 nΩ·m
Thermal Conductivity 237 W·m−1·K−1
Thermal Expansion (25 °C) 23.1 µm·m−1·K−1
Speed of Sound (r.t.) (rolled) 5,000 m·s
Young's Modulus 70 GPa
Shear Modulus 26 GPa
Bulk Modulus 76 GPa
Poisson Ratio 0.35
Mohs Hardness 2.75
Vickers Hardness 167 MPa
Brinell Hardness 245 MPa
CAS Registry Number 7429-90-5
Al
General Properties
Name Silicon
Symbol Si
Atomic Number 14
Pronunciation /ˈsɪlɨkən/ sil-ə-kən or /ˈsɪlɨkɒn/ sil-ə-kon
Element Category metalloid
Group 14
Period 3
Block p
Atomic Weight 28.0855(3)
Electron Configuration [Ne] 3s2 3p2
Electrons Per Shell 2, 8, 4
Atomic Properties
Oxidation States 4, 3 , 2 , 1 -1, -2, -3, -4 (amphoteric oxide)
Electronegativity 1.90 (Pauling scale)
Ionization Energies 1st: 786.5 kJ·mol−1
2nd: 1577.1 kJ·mol−1
3rd: 3231.6 kJ·mol−1
Atomic Radius 111 pm
Covalent Radius 111 pm
Van der Waals Radius 210 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1908 2102 2339 2636 3021 3537
Physical Properties
Phase solid
Density (near r.t.) 2.3290 g·cm−3
Liquid Density at m.p. 2.57 g·cm−3
Melting Point 1687 K,1414 °C,2577 °F
Boiling Point 3538 K,3265 °C,5909 °F
Heat of Fusion 50.21 kJ·mol−1
Heat of Vaporization 359 kJ·mol−1
Molar Heat Capacity 19.789 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
28Si 92.23% 28Si is stable with 14 neutrons
29Si 4.67% 29Si is stable with 15 neutrons
30Si 3.1% 30is stable with 16 neutrons
32Si trace 170 y β− 13.020 32P
Miscellanea
Crystal Structure diamond cubic
Magnetic Ordering diamagnetic
Electrical Resistivity (20 °C) 103 Ω·m
Thermal Conductivity 149 W·m−1·K−1
Thermal Expansion (25 °C) 2.6 µm·m−1·K−1
Speed of Sound (20 °C) 8433 m·s
Young's Modulus 185 GPa
Shear Modulus 52 GPa
Bulk Modulus 100 GPa
Poisson Ratio 0.28
Mohs Hardness 7
CAS Registry Number 7440-21-3
Band gap energy at 300 K 1.12 eV
Si
General Properties
Name Phosphorus
Symbol P
Atomic Number 15
Pronunciation /ˈfɒsfərəs/ fos-fər-əs
Element Category nonmetal
Group 15
Period 3
Block p
Atomic Weight 30.973762(2)
Electron Configuration [Ne] 3s2 3p3
Electrons Per Shell 2, 8, 5
Atomic Properties
Oxidation States 5, 4, 3, 2, 1 , -1, -2, -3 (mildly acidic oxide)
Electronegativity 2.19 (Pauling scale)
Ionization Energies 1st: 1011.8 kJ·mol−1
2nd: 1907 kJ·mol−1
3rd: 2914.1 kJ·mol−1
Covalent Radius 107±3 pm
Van der Waals Radius 180 pm
Vapour Pressure(White)
P (Pa) 1 10 100 1K 10K 100K
at T (K) 279 307 342 388 453 549
Vapour Pressure (red, bp. 431 °C)
P (Pa) 1 10 100 1K 10K 100K
at T (K) 455 489 529 576 635 704
Physical Properties
Density (white) 1.823, (red) ≈ 2.2 – 2.34, (violet) 2.36, (black) 2.69 g·cmM−3
Melting Point (white) 44.2 °C, (black) 610 °C
Sublimation Point (red) ≈ 416 – 590 °C, (violet) 620 °C
Boiling Point (white) 280.5 °C
Heat of Fusion (white) 0.66 kJ·mol−1
Heat of Vaporization (white) 12.4 kJ·mol−1
Molar Heat Capacity (white) 23.824 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
31P 100% 31P is stable with 16 neutrons
32P syn 14.28 d β− 1.709 32S
33P syn 25.3 d β− 0.249 33S
Miscellanea
Magnetic Ordering (white,red,violet,black) diamagnetic
Thermal Conductivity (white) 0.236, (black) 12.1 W·m−1·K−1
Bulk Modulus (white) 5, (red) 11 GPa
CAS Registry Number 7723-14-0
P
General Properties
Name Sulfur
Symbol S
Atomic Number 16
Pronunciation /ˈsʌlfər/ sul-fər
Element Category nonmetal
Group 16
Period 3
Block p
Atomic Weight 32.065(5)
Electron Configuration [Ne] 3s2 3p4
Electrons Per Shell 2, 8, 6
Atomic Properties
Oxidation States 6, 5, 4, 3, 2, 1, -1, -2 (strongly acidic oxide)
Electronegativity 2.58 (Pauling scale)
Ionization Energies 1st: 999.6 kJ·mol−1
2nd: 2252 kJ·mol−1
3rd: 3357 kJ·mol−1
Covalent Radius 105±3 pm
Van der Waals Radius 180 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 375 408 449 508 591 717
Physical Properties
Phase solid
Density (alpha) 2.07 g·cm−3
Liquid Density at m.p. 1.819 g·cm−3
Melting Point 388.36 K,115.21 °C,239.38 °F
Boiling Point 717.8 K,444.6 °C,832.3 °F
Critical Point 1314 K, 20.7 MPa
Heat of Fusion (mono) 1.727 kJ·mol−1
Heat of Vaporization (mono) 45 kJ·mol−1
Molar Heat Capacity 22.75 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
32S 95.02% 32S is stable with 16 neutrons
33S 0.75% 33S is stable with 17 neutrons
34S 4.21% 34S is stable with 18 neutrons
35S syn 87.32 d β− 0.167 35Cl
36 0.02% 36S is stable with 20 neutrons
Miscellanea
Crystal Structure orthorhombic
Magnetic Ordering diamagnetic
Electrical Resistivity (20 °C) (amorphous) 2*1015 Ω·m
Thermal Conductivity (amorphous) 0.205 W·m−1·K−1
Bulk Modulus 7.7 GPa
Mohs Hardness 2.0
CAS Registry Number 7704-34-9
S
General Properties
Name Chlorine
Symbol Cl
Atomic Number 17
Pronunciation /ˈklɔəriːn/ klor-een
Element Category halogen
Group 17
Period 3
Block p
Atomic Weight 35.453(2)
Electron Configuration [Ne] 3s2 3p5
Electrons Per Shell 2, 8, 7
Atomic Properties
Oxidation States 7, 6, 5, 4, 3, 2, 1, -1 (strongly acidic oxide)
Electronegativity 3.16 (Pauling scale)
Ionization Energies 1st: 1251.2 kJ·mol−1
2nd: 2298 kJ·mol−1
3rd: 3822 kJ·mol−1
Covalent Radius 102±4 pm
Van der Waals Radius 175 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 128 139 153 170 197 239
Physical Properties
Phase gas
Density (0 °C, 101.325 kPa) 3.2 g/L
Liquid Density at b.p. 1.5625 g·cm−3
Melting Point 171.6 K,-101.5 °C,-150.7 °F
Boiling Point 239.11 K,-34.04 °C,-29.27 °F
Critical Point 416.9 K, 7.991 MPa
Heat of Fusion (Cl2) 6.406 kJ·mol−1
Heat of Vaporization (Cl2) 20.41 kJ·mol−1
Molar Heat Capacity (Cl2) 33.949 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
35Cl 75.77% 35Cl is stable with 18 neutrons
36Cl trace 3.01*105 y β− 0.709 36Ar
ε - 36S
37Cl 24.23% 37Cl is stable with 20 neutrons
Miscellanea
Crystal Structure orthorhombic
Magnetic Ordering diamagnetic[2]
Electrical Resistivity (20 °C) > 10 Ω·m
Thermal Conductivity 8.9*10−3 W·m−1·K−1
Speed of Sound (gas, 0 °C) 206 m·s
CAS Registry Number 7782-50-5
Cl
General Properties
Name Argon
Symbol Ar
Atomic Number 18
Pronunciation /ˈɑrɡɒn/
Element Category noble gases
Group 18
Period 3
Block p
Atomic Weight 39.948(1)
Electron Configuration [Ne] 3s2 3p6
Electrons Per Shell 2, 8, 8
Atomic Properties
Oxidation States 0
Electronegativity no data (Pauling scale)
Ionization Energies 1st: 1520.6 kJ·mol−1
2nd: 2665.8 kJ·mol−1
3rd: 3931 kJ·mol−1
Covalent Radius 106±10 pm
Van der Waals Radius 188 pm
Miscellanea
Crystal Structure face-centered cubic
Magnetic Ordering diamagnetic
Thermal Conductivity 17.72x10-3 W·m−1·K−1
Speed of Sound (gas, 27 °C) 323 m·s
CAS Registry Number 7440–37–1
Physical Properties
Phase gas
Density (0 °C, 101.325 kPa) 1.784 g/L
Liquid Density at b.p. 1.40 g·cm−3
Melting Point 83.80 K,-189.35 °C,−308.83 °F
Boiling Point 87.30 K,-185.85 °C,−302.53 °F
Triple Point 83.8058 K (-189°C), 69 kPa
Critical Point 150.87 K, 4.898 MPa
Heat of Fusion 1.18 kJ·mol−1
Heat of Vaporization 6.43 kJ·mol−1
Molar Heat Capacity 5R/2 = 20.786 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
36Ar 0.337% 36Ar is stable with 18 neutrons
37Ar syn 35 d ε 0.813 37Cl
38Ar 0.063% 38Ar is stable with 20 neutrons
39Ar trace 269 y β− 0.565 39K
40Ar 99.600% 40Ar is stable with 22 neutrons
41Ar syn 109.34 min β− 2.49 41K
42Ar syn 32.9 y β− 0.600 42K
Vapour Pressure
P (Pa)
at T (K) 47 53 61 71 87
Ar
4
General Properties
Name Potassium
Symbol K
Atomic Number 19
Pronunciation /pɵˈtæsiəm/ po-tas-ee-əm
Element Category alkali metal
Group 1
Period 4
Block s
Atomic Weight 39.0983(1)
Electron Configuration [Ar] 4s1
Electrons Per Shell 2, 8, 8, 1
Atomic Properties
Oxidation States 1 (strongly basic oxide)
Electronegativity 0.82 (Pauling scale)
Ionization Energies 1st: 418.8 kJ·mol−1
2nd: 3052 kJ·mol−1
3rd: 4420 kJ·mol−1
Atomic Radius 227 pm
Covalent Radius 203±12 pm
Van der Waals Radius 275 pm
Miscellanea
Crystal Structure body-centered cubic
Magnetic Ordering paramagnetic
Electrical Resistivity (20 °C) 72 nΩ·m
Thermal Conductivity 102.5 W·m−1·K−1
Thermal Expansion (25 °C) 83.3 µm·m−1·K−1
Speed of Sound (20 °C) 2000 m·s
Young's Modulus 3.53 GPa
Shear Modulus 1.3 GPa
Bulk Modulus 3.1 GPa
Mohs Hardness 0.4
Brinell Hardness 0.363 MPa
CAS Registry Number 7440-09-7
Physical Properties
Phase solid
Density 0.862 g·cm−3
Liquid Density at m.p. 0.828 g·cm−3
Melting Point 336.53 K,63.38 °C,146.08 °F
Boiling Point 1032 K,759 °C,1398 °F
Triple Point 336.35 K (63°C), kPa
Heat of Fusion 2.33 kJ·mol−1
Heat of Vaporization 76.9 kJ·mol−1
Molar Heat Capacity 29.6 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
39K 93.26% 39K is stable with 20 neutrons
40K 0.012% 1.248(3)—109 y β− 1.311 40Ca
ε 1.505 40Ar
β+ 1.505 40Ar
41K 6.73% 41K is stable with 22 neutrons
K
General Properties
Name Calcium
Symbol Ca
Atomic Number 20
Pronunciation /ˈkælsiəm/ kal-see-əm
Element Category alkaline earth metal
Group 2
Period 4
Block s
Atomic Weight alkaline earth metal
Electron Configuration [Ar] 4s2
Electrons Per Shell 2, 8, 8, 2
Atomic Properties
Oxidation States +2, +1 (strongly basic oxide)
Electronegativity 1.00 (Pauling scale)
Ionization Energies 1st: 589.8 kJ·mol−1
2nd: 1145.4 kJ·mol−1
3rd: 4912.4 kJ·mol−1
Atomic Radius 197 pm
Covalent Radius 176±10 pm
Van der Waals Radius 231 pm
Miscellanea
Crystal Structure face-centered cubic
Magnetic Ordering diamagnetic
Electrical Resistivity (20 °C) 33.6 nΩ·m
Thermal Conductivity 201 W·m−1·K−1
Thermal Expansion (25 °C) 22.3 µm·m−1·K−1
Speed of Sound (20 °C) 3810 m·s
Young's Modulus 20 GPa
Shear Modulus 7.4 GPa
Bulk Modulus 17 GPa
Poisson Ratio 0.31
Mohs Hardness 1.75
Brinell Hardness 167 MPa
CAS Registry Number 7440-70-2
Physical Properties
Color
Phase Solid
Density(near r.t.) 1.55 g·cm−3
Liquid Density at m.p. 1.378 g·cm−3
Melting Point 1115 K, 842 °C, 1548 °F
Boiling Point 1757 K, 1484 °C, 2703 °F
Heat of Fusion 8.54 kJ·mol−1
Heat of Vaporization 154.7 kJ·mol−1
Molar Heat Capacity 25.929 J·mol−1·K−1
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
40Ca a 96.941% 40Ca is stable with 20 neutrons
41Ca trace 1.03*105 y ε - 41K
42Ca 0.647% 42Ca is stable with 22 neutrons
43Ca 0.135% 43Ca is stable with 23 neutrons
44Ca 2.086% 44Ca is stable with 24 neutrons
45Ca syn 162.7 d β− 0.258 45Sc
46Ca 0.004% >2.8*1015 y β−β− ? 46Ti
47Ca syn 4.536 d β− 0.694, 1.99 47Sc
γ 1.297 -
48Ca 0.187% >4*1019 y β−β− ? 48Ti
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 864 956 1071 1227 1443 1755
Ca
General Properties
Name Scandium
Symbol Sc
Atomic Number 21
Pronunciation /ˈskændiəm/ skan-dee-əm
Element Category transition metal
Group 3
Period 4
Block d
Atomic Weight 44.955912(6)
Electron Configuration [Ar] 3d1 4s2
Electrons Per Shell 2, 8, 9, 2
Atomic Properties
Oxidation States 3, 2, 1 (amphoteric oxide)
Electronegativity 1.36 (Pauling scale)
Ionization Energies 1st: 633.1 kJ·mol−1
2nd: 1235.0 kJ·mol−1
3rd: 2388.6 kJ·mol−1
Atomic Radius 162 pm
Covalent Radius 170±7 pm
Van der Waals Radius 211 pm
Miscellanea
Crystal Structure hexagonal
Magnetic Ordering paramagnetic
Electrical resistivity (r.t.) (α, poly) calc. 562 nΩ·m
Thermal Conductivity 15.8 W·m−1·K−1
Thermal Expansion (r.t.) (α, poly) 10.2 µm/(m·K)
Speed of Sound (20 °C) 3810 m·s
Young's Modulus 74.4 GPa
Shear Modulus 29.1 GPa
Bulk Modulus 56.6 GPa
Poisson Ratio 0.279
Brinell Hardness 750 MPa
CAS Registry Number 7440-20-2
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) ) 1645 1804 (2006) (2266 (2613) (3101)
Physical Properties
Phase solid
Density 2.985 g·cm−3
Liquid Density at m.p. 2.80 g·cm−3
Melting Point 1814 K,1541 °C,2806 °F
Boiling Point 3109 K,2836 °C,5136 °F
Heat of Fusion 14.1 kJ·mol−1
Heat of Vaporization 332.7 kJ·mol−1
Molar Heat Capacity 25.52 J·mol·K-1
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
44Sc syn 58.61 h IT 0.2709 44Sc
γ 1.0, 1.1, 1.1 44Sc
ε - 44Ca
45Sc 100% 45Sc is stable with 24 neutrons
46Sc syn 83.79 d β− 0.3569 46Ti
γ 0.889, 1.120 -
47Sc syn 3.3492 d β− 0.44, 0.60 47Ti
γ 0.159 -
48Sc syn 43.67 h β− 0.661 48Ti
γ 0.9, 1.3, 1.0 -
Sc
General Properties
Name Titanium
Symbol Ti
Atomic Number 22
Pronunciation /taɪˈteɪniəm/ tye-tay-nee-əm
Element Category transition metal
Group 4
Period 4
Block d
Atomic Weight 47.867(1)
Electron Configuration [Ar] 4s2 3d2
Electrons Per Shell 2, 8, 10, 2
Atomic Properties
Oxidation States 4, 3, 2, 1 (amphoteric oxide)
Electronegativity 1.54 (Pauling scale)
Ionization Energies 1st: 658.8 kJ·mol−1
2nd: 1309.8 kJ·mol−1
3rd: 2652.5 kJ·mol−1
Atomic Radius 147 pm
Covalent Radius 160±8 pm
Miscellanea
Crystal Structure hexagonal
Magnetic Ordering paramagnetic
Electrical resistivity (20 °C) 420 nΩ·m
Thermal Conductivity 21.9 W·m−1·K−1
Thermal Expansion (25 °C) 8.6 µm·m−1·K−1
Speed of Sound (r.t.) 5,090 m·s
Young's Modulus 116 GPa
Shear Modulus 44 GPa
Bulk Modulus 110 GPa
Poisson Ratio 0.32
Mohs Hardness 6.0
Vickers Hardness 970 MPa
Brinell Hardness 716 MPa
CAS Registry Number 7440-32-6
Physical Properties
Phase solid
Density (near r.t.) 4.506 g·cm−3
Liquid Density at m.p. 4.11 g·cm−3
Melting Point 1941 K,1668 °C,3034 °F
Boiling Point 3560 K,3287 °C,5949 °F
Heat of Fusion 14.15 kJ·mol−1
Heat of Vaporization 425 kJ·mol−1
Molar Heat Capacity 25.060 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
44Ti syn 63 y ε - 44Sc
γ 0.07D, 0.08D -
46Ti 8.0% 46Ti is stable with 24 neutrons
47Ti 7.3% 47Ti is stable with 25 neutrons
48Ti 73.8% 48Ti is stable with 26 neutrons
49Ti 5.5% 49Ti is stable with 27 neutrons
50Ti i 5.4% 50Ti is stable with 28 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1982 2171 (2403) 2692 3064 3558
Ti
General Properties
Name Vanadium
Symbol V
Atomic Number 23
Pronunciation /vəˈneɪdiəm/ və-nay-dee-əm
Element Category transition metal
Group 5
Period 4
Block d
Atomic Weight 50.9415(1)
Electron Configuration [Ar] 3d3 4s2
Electrons Per Shell 2, 8, 11, 2
Atomic Properties
Oxidation States 5, 4, 3, 2, 1, -1 (amphoteric oxide)
Electronegativity 1.63 (Pauling scale)
Ionization Energies 1st: 650.9 kJ·mol−1
2nd: 1414 kJ·mol−1
3rd: 2830 kJ·mol−1
Atomic Radius 134 pm
Covalent Radius 153±8 pm
Miscellanea
Crystal Structure body-centered cubic
Magnetic Ordering paramagnetic
Electrical Resistivity (20 °C) 197 nΩ·m
Thermal Conductivity 30.7 W·m−1·K−1
Thermal Expansion (25 °C) 8.4 µm·m−1·K−1
Speed of Sound (20 °C) 4560 m·s
Young's Modulus 128 GPa
Shear Modulus 47 GPa
Bulk Modulus 160 GPa
Poisson Ratio 0.37
Mohs Hardness 6.7
CAS Registry Number 7440-62-2
Physical Properties
Phase solid
Density (near r.t.) 6.0 g·cm−3
Liquid Density at m.p. 5.5 g·cm−3
Melting Point 2183 K,1910 °C,3470 °F
Boiling Point 3680 K,3407 °C,6165 °F
Heat of Fusion 21.5 kJ·mol−1
Heat of Vaporization 459 kJ·mol−1
Molar Heat Capacity 24.89 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
48V syn 15.9735 d ε+β+ 4.0123 48Ti
49V syn 330 d ε 0.6019 49Ti
50V 0.25% 1.5*1017y ε 2.2083 50Ti
β− 1.0369 50Cr
51V 99.75% 51V is stable with 28 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 2101 2289 2523 2814 3187 3679
V
General Properties
Name Chromium
Symbol Cr
Atomic Number 24
Pronunciation /ˈkroʊmiəm/ kroh-mee-əm
Element Category transition metal
Group 6
Period 4
Block d
Atomic Weight 51.9961(6)
Electron Configuration [Ar] 3d5 4s1
Electrons Per Shell 2, 8, 13, 1
Atomic Properties
Oxidation States 6, 5, 4, 3, 2, 1, -1, -2 (strongly acidic oxide)
Electronegativity 1.66 (Pauling scale)
Ionization Energies 1st: 652.9 kJ·mol−1
2nd: 1590.6 kJ·mol−1
3rd: 2987 kJ·mol−1
Atomic Radius 128 pm
Covalent Radius 139±5 pm
Miscellanea
Crystal Structure body-centered cubic
Magnetic Ordering AFM (rather: SDW )
Electrical Resistivity (20 °C) 125 nΩ·m
Thermal Conductivity 93.9 W·m−1·K−1
Thermal Expansion (25 °C) 4.9 µm·m−1·K−1
Speed of Sound (20 °C) 5940 m·s
Young's Modulus 279 GPa
Shear Modulus 115 GPa
Bulk Modulus 160 GPa
Poisson Ratio 0.21
Mohs Hardness 8.5
Vickers Hardness 1060 MPa
Brinell Hardness 1120 MPa
CAS Registry Number 7440-47-3
Physical Properties
Phase solid
Density (near r.t.) 7.19 g·cm−3
Liquid Density at m.p. 6.3 g·cm−3
Melting Point 2180 K,1907 °C,3465 °F
Boiling Point 2944 K,2671 °C,4840 °F
Heat of Fusion 21.0 kJ·mol−1
Heat of Vaporization 339.5 kJ·mol−1
Molar Heat Capacity 23.35 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
50Cr 4.345% > 1.8*1017y εε - 50Ti
51Cr syn 27.7025 d ε - 51V
γ 0.320 -
52Cr 83.789% 52Cr is stable with 28 neutrons
53Cr 9.501% 53Cr is stable with 29 neutrons
54Cr 2.365% 54Cr is stable with 30 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1656 1807 1991 2223 2530 2942
Cr
General Properties
Name Manganese
Symbol Mn
Atomic Number 25
Pronunciation /ˈmæŋɡəniːz/ mang-gən-neez
Element Category transition metal
Group 7
Period 4
Block d
Atomic Weight 54.938045(5)
Electron Configuration [Ar] 4s2 3d5
Electrons Per Shell 2, 8, 13, 2
Atomic Properties
Oxidation States 7, 6, 5, 4, 3, 2, 1, -1, -2, -3 (oxides: acidic, basic or amphoteric depending on the oxidation state)
Electronegativity 1.55 (Pauling scale)
Ionization Energies 1st: 717.3 kJ·mol−1
2nd: 1509.0 kJ·mol−1
3rd: 3248 kJ·mol−10.02591[15] W·m−1·K−1
Atomic Radius 127 pm
Covalent Radius 139±5 (low spin), 161±8 (high spin) pm
Miscellanea
Crystal Structure body-centered cubic
Magnetic Ordering paramagnetic
Electrical Resistivity (20 °C) 1.44 µΩ·m
Thermal Conductivity 7.81 W·m−1·K−1
Thermal Expansion (25 °C) 21.7 µm·m−1·K−1
Speed of Sound (20 °C) 5150 m·s
Young's Modulus 198 GPa
Bulk Modulus 120 GPa
Mohs Hardness 6.0
Brinell Hardness 196 MPa
CAS Registry Number 7439-96-5
Physical Properties
Phase solid
Density (near r.t.) 7.21 g·cm−3
Liquid Density at m.p. 5.95 g·cm−3
Melting Point 1519 K,1246 °C,2275 °F
Boiling Point 2334 K,2061 °C,3742 °F
Heat of Fusion 12.91 kJ·mol−1
Heat of Vaporization 221 kJ·mol−1
Molar Heat Capacity 26.32 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
52Mn syn 5.591 d ε - 52Cr
β+ 0.575 52Cr
γ 0.7, 0.9, 1.4 -
53Mn trace 3.74 *106 y ε - 53Cr
54Mn syn 312.3 d ε 1.377 54Cr
γ 0.834 -
55Mn 100% 55Mn is stable with 30 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1228 1347 1493 1691 1955 2333
Mn
General Properties
Name Iron
Symbol Fe
Atomic Number 26
Pronunciation /ˈaɪ.ərn/
Element Category transition metal
Group 8
Period 4
Block d
Atomic Weight 55.845(2)
Electron Configuration [Ar] 3d6 4s2
Electrons Per Shell 2, 8, 14, 2
Atomic Properties
Electronegativity 1.83 (Pauling scale)
Ionization Energies 1st: 762.5 kJ·mol−1
2nd: 1561.9 kJ·mol−1
3rd: 2957 kJ·mol−1
Atomic Radius 126 pm
Covalent Radius 132±3 (low spin), 152±6 (high spin) pm
Miscellanea
Crystal Structure body-centered cubic
Magnetic Ordering ferromagnetic 1043 K
Electrical Resistivity (20 °C) 96.1 nΩ·m
Thermal Conductivity 80.4 W·m−1·K−1
Thermal Expansion (25 °C) 11.8 µm·m−1·K−1
Speed of Sound (r.t.) (electrolytic) 5120 m·s
Young's Modulus 211 GPa
Shear Modulus 82 GPa
Bulk Modulus 170 GPa
Poisson Ratio 0.29
Mohs Hardness 4
Vickers Hardness 608 MPa
Brinell Hardness 490 MPa
CAS Registry Number 7439-89-6
Physical Properties
Phase solid
Density (near r.t.) 7.874 g·cm−3
Liquid Density at m.p. 6.98 g·cm−3
Melting Point 1811 K,1538 °C,2800 °F
Boiling Point 3134 K,2862 °C,5182 °F
Heat of Fusion 13.81 kJ·mol−1
Heat of Vaporization 340 kJ·mol−1
Molar Heat Capacity 25.10 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
54Fe 5.8% >3.1*1022y 2ε capture ? 54Cr
55Fe syn 2.73 y ε capture 0.231 55Mn
56Fe 91.72% 56Fe is stable with 30 neutrons
57Fe 2.2% 57Fe is stable with 31 neutrons
58Fe 0.28% 58Fe is stable with 32 neutrons
59Fe syn 44.503 d β− 1.565 59Co
60Fe syn 2.6*106 y β− 3.978 60Co
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1728 1890 2091 2346 2679 3132
Fe
General Properties
Name Cobalt
Symbol Co
Atomic Number 27
Pronunciation /ˈkoʊbɒlt/ koh-bolt
Element Category transition metal
Group 9
Period 4
Block d
Atomic Weight 58.933195(5)
Electron Configuration [Ar] 4s2 3d7
Electrons Per Shell 2, 8, 15, 2
Atomic Properties
Oxidation States 5, 4 , 3, 2, 1, -1 (amphoteric oxide)
Electronegativity 1.88 (Pauling scale)
Ionization Energies 1st: 760.4 kJ·mol−1
2nd: 1648 kJ·mol−1
3rd: 3232 kJ·mol−1
Atomic Radius 125 pm
Covalent Radius 126±3 (low spin), 150±7 (high spin) pm
Miscellanea
Crystal Structure hexagonal
Magnetic Ordering ferromagnetic
Electrical Resistivity (20 °C) 62.4 nΩ·m
Thermal Conductivity 100 W·m−1·K−1
Thermal Expansion (25 °C) 13.0 µm·m−1·K−1
Speed of Sound (20 °C) 4720 m·s
Young's Modulus 209 GPa
Shear Modulus 75 GPa
Bulk Modulus 180 GPa
Poisson Ratio 0.31
Mohs Hardness 5.0
Vickers Hardness 1043 MPa
Brinell Hardness 700 MPa
CAS Registry Number 7440-48-4
Physical Properties
Color metallic gray
Density 8.90 g·cm−3
Liquid Density at m.p. 7.75 g·cm−3
Melting Point 1768 K,1495 °C,2723 °F
Boiling Point 3200 K,2927 °C,5301 °F
Triple Point
Critical Point
Heat of Fusion 16.06 kJ·mol−1
Heat of Vaporization 377 kJ·mol−1
Molar Heat Capacity 24.81 J·mol·
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
56Co syn 77.27 d ε 4.566 56Fe
57Co syn 271.79 d ε 0.836 57Fe
58Co syn 70.86 d ε 2.307 58Fe
59Co 100% 59Co is stable with 32 neutrons
60Co syn 5.2714 years β−, γ, γ 2.824 60Ni
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1790 1960 2165 2423 2755 3198
Co
General Properties
Name Nickel
Symbol Ni
Atomic Number 28
Pronunciation /ˈnɪkəl/
Element Category transition metal
Group 10
Period 4
Block d
Atomic Weight 58.6934(4)(2)
Electron Configuration [Ar] 4s2 3d8 or [Ar] 4s1 3d9
Electrons Per Shell 2, 8, 16, 2 or 2, 8, 17, 1
Atomic Properties
Oxidation States 4, 3, 2, 1 , -1 (mildly basic oxide)
Electronegativity 1.91 (Pauling scale)
Ionization Energies 1st: 737.1 kJ·mol−1
2nd: 1753.0 kJ·mol−1
3rd: 3395 kJ·mol−1
Atomic Radius 124 pm
Covalent Radius 124±4 pm
Van der Waals Radius 163 pm
Miscellanea
Crystal Structure face-centered cubic
Magnetic Ordering ferromagnetic
Electrical Resistivity (20 °C) 69.3 nΩ·m
Thermal Conductivity 90.9 W·m−1·K−1
Thermal Expansion (25 °C) 13.4 µm·m−1·K−1
Speed of Sound (r.t.) 4900 m·s
Young's Modulus 200 GPa
Shear Modulus 76 GPa
Bulk Modulus 180 GPa
Poisson Ratio 0.31
Mohs Hardness 4.0
Vickers Hardness 638 MPa
Brinell Hardness 700 MPa
CAS Registry Number 7440-02-0
Physical Properties
Phase solid
Density (near r.t.) 8.908 g·cm−3
Liquid Density at m.p. 7.81 g·cm−3
Melting Point 1728 K,1455 °C,2651 °F
Boiling Point 3186 K,2913 °C,5275 °F
Heat of Fusion 17.48 kJ·mol−1
Heat of Vaporization 377.5 kJ·mol−1
Molar Heat Capacity 26.07 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
58Ni 68.077% 58Ni is stable with 30 neutrons
59Ni trace 76000 y ε - 59Co
60Ni 26.223% 60Ni is stable with 32 neutrons
61Ni 1.14% 61Ni is stable with 33 neutrons
62Ni 3.634% 62Ni is stable with 34 neutrons
63Ni syn 100.1 y β− 0.0669 63Cu
64Ni 0.926% 64Ni is stable with 36 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1783 1950 2154 2410 2741 3184
Ni
General Properties
Name Copper
Symbol Cu
Atomic Number 29
Pronunciation /ˈkɒpər/ kop-ər
Element Category transition metal
Group 11
Period 4
Block d
Atomic Weight 63.546(3)
Electron Configuration [Ar] 4s1 3d10
Electrons Per Shell 2, 8, 18, 1
Atomic Properties
Oxidation States +1, +2, +3, +4 (mildly basic oxide)
Electronegativity 1.90 (Pauling scale)
Ionization Energies 1st: 745.5 kJ·mol−1
2nd: 1957.9 kJ·mol−1
3rd: 3555 kJ·mol−1
Atomic Radius 128 pm
Covalent Radius 132±4 pm
Van der Waals Radius 140 pm
Miscellanea
Crystal Structure face-centered cubic
Magnetic Ordering diamagnetic
Electrical Resistivity (20 °C) 16.78 nΩ·m
Thermal Conductivity 401 W·m−1·K−1
Thermal Expansion (25 °C) 11.8 µm·m−1·K−1
Speed of Sound (r.t.) (annealed) 3810 m·s
Young's Modulus 110–128 GPa
Shear Modulus 48 GPa
Bulk Modulus 140 GPa
Poisson Ratio 0.34
Mohs Hardness 3.0
Vickers Hardness 369 MPa
Brinell Hardness 874 MPa
CAS Registry Number 7440-50-8
Physical Properties
Phase solid
Density (near r.t.) 8.94 g·cm−3
Liquid Density at m.p. 8.02 g·cm−3
Melting Point 1357.77 K,1084.62 °C,1984.32 °F
Boiling Point 2835 K,2562 °C,4643 °F
Heat of Fusion 13.26 kJ·mol−1
Heat of Vaporization 300.4 kJ·mol−1
Molar Heat Capacity 24.440 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
63Cu 69.15% 63Cu is stable with 34 neutrons
65Cu 30.85% 65Cu is stable with 36 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1509 1661 1850 2089 2404 2834
Cu
General Properties
Name Zinc
Symbol Zn
Atomic Number 30
Pronunciation /ˈzɪŋk/ zingk
Element Category transition metal
Group 12
Period 4
Block d
Atomic Weight 65.38(2)(4)
Electron Configuration [Ar] 3d10 4s2
Electrons Per Shell 2, 8, 18, 2
Atomic Properties
Oxidation States +2, +1, 0 (amphoteric oxide)
Electronegativity 1.65 (Pauling scale)
Ionization Energies 1st: 906.4 kJ·mol−1
2nd: 1733.3 kJ·mol−1
3rd: 3833 kJ·mol−1
Atomic Radius 134 pm
Covalent Radius 122±4 pm
Van der Waals Radius 139 pm
Miscellanea
Crystal Structure hexagonal
Magnetic Ordering diamagnetic
Electrical Resistivity (20 °C) 59.0 nΩ·m
Thermal Conductivity 116 W·m−1·K−1
Thermal Expansion (25 °C) 30.2 µm·m−1·K−1
Speed of Sound (r.t.) (rolled) 3850 m·s
Young's Modulus 108 GPa
Shear Modulus 43 GPa
Bulk Modulus 70 GPa
Poisson Ratio 0.25
Mohs Hardness 2.5
Brinell Hardness 412 MPa
CAS Registry Number 7440-66-6
Physical Properties
Phase solid
Density (near r.t.) 7.14 g·cm−3
Liquid Density at m.p. 6.57 g·cm−3
Melting Point 692.68 K,419.53 °C,787.15 °F
Boiling Point 1180 K,907 °C,1665 °F
Heat of Fusion 7.32 kJ·mol−1
Heat of Vaporization 123.6 kJ·mol−1
Molar Heat Capacity 25.470 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
64Zn 48.6% 64Zn is stable with 34 neutrons
65Zn syn 243.8 d ε 1.3519 65Cu
γ 1.1155 -
66Zn 27.9% 66Zn is stable with 36 neutrons
67Zn 4.1% 67Zn is stable with 37 neutrons
68Zn 18.8% 68Zn is stable with 38 neutrons
70Zn 0.6% 70Zn is stable with 40 neutrons
72Zn syn 46.5 h β− 0.458 72Ga
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 610 670 750 852 990 1179
Zn
General Properties
Name Gallium
Symbol Ga
Atomic Number 31
Pronunciation /ˈɡæliəm/ gal-ee-əm
Element Category post-transition metal
Group 13
Period 4
Block p
Atomic Weight 69.723(1)
Electron Configuration [Ar] 4s2 3d10 4p1
Electrons Per Shell 2, 8, 18, 3
Atomic Properties
Oxidation States 3, 2, 1 (amphoteric oxide)
Electronegativity 1.81 (Pauling scale)
Ionization Energies 1st: 578.8 kJ·mol−1
2nd: 1979.3 kJ·mol−1
3rd: 2963 kJ·mol−1
Atomic Radius 135 pm
Covalent Radius 122±3 pm
Van der Waals Radius 187 pm
Miscellanea
Crystal Structure orthorhombic
Magnetic Ordering orthorhombic
Electrical resistivity (20 °C) 270 nΩ·m
Thermal Conductivity 40.6 W·m−1·K−1
Thermal Expansion (25 °C) 1.2 µm·m−1·K−1
Speed of Sound (20 °C) 2740 m·s
Young's Modulus 9.8 GPa
Poisson Ratio 0.47
Mohs Hardness 1.5
Brinell Hardness 60 MPa
CAS Registry Number 7440-55-3
Physical Properties
Phase solid
Density (near r.t.) 5.91 g·cm−3
Liquid Density at m.p. 6.095 g·cm−3
Melting Point 302.9146 K,29.7646 °C,85.5763 °F
Boiling Point 2477 K,2204 °C,3999 °F
Heat of Fusion 5.59 kJ·mol−1
Heat of Vaporization 254 kJ·mol−1
Molar Heat Capacity 25.86 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
69Ga 60.11% 69Ga is stable with 38 neutrons
71Ga 39.89% 71Ga is stable with 40 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1310 1448 1620 1838 2125 2518
Ga
General Properties
Name Germanium
Symbol Ge
Atomic Number 32
Pronunciation /dʒərˈmeɪniəm/ jər-may-nee-əm
Element Category metalloid
Group 14
Period 4
Block p
Atomic Weight 72.63(1)
Electron Configuration [Ar] 3d10 4s2 4p2
Electrons Per Shell 2, 8, 18, 4
Atomic Properties
Oxidation States 4, 3, 2, 1, 0, -1, -2, -3, -4 (amphoteric oxide)
Electronegativity 2.01 (Pauling scale)
Ionization Energies 1st: 762 kJ·mol−1
2nd: 1537.5 kJ·mol−1
3rd: 3302.1 kJ·mol−1
Atomic Radius 122 pm
Covalent Radius 122 pm
Van der Waals Radius 211 pm
Miscellanea
Crystal Structure Diamond cubic
Magnetic Ordering Diamagnetic
Electrical resistivity (20 °C) 1 Ω·m
Thermal Conductivity 60.2 W·m−1·K−1
Thermal Expansion 6.0 µm/(m·K)
Speed of Sound (20 °C) 5400 m·s−1
Young's Modulus 103 GPa
Shear Modulus 41 GPa
Bulk Modulus 75 GPa
Poisson Ratio 0.26
Mohs Hardness 6.0
CAS Registry Number 7440-56-4
Band gap energy at 300 K 0.67 eV
Physical Properties
Phase solid
Density (near r.t.) 5.323 g·cm−3
Liquid Density at m.p. 5.60 g·cm
Melting Point 1211.40 K,938.25 °C,1720.85 °F
Boiling Point 3106 K,2833 °C,5131 °F
Heat of Fusion 36.94 kJ·mol−1
Heat of Vaporization 334 kJ·mol−1
Molar Heat Capacity 23.222 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
68Ge syn 270.8 d ε - 68Ga
70Ge 21.23% 70Ge is stable with 38 neutrons
71Ge syn 11.26 d ε - 71Ga
72Ge 27.66% 72Ge is stable with 40 neutrons
73Ge 7.73% 73Ge is stable with 41 neutrons
74Ge 35.94% 74Ge is stable with 42 neutrons
76Ge 7.44% 1.78*1021 y β−β− - 76Se
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1644 1814 2023 2287 2633 3104
Ge
General Properties
Name Arsenic
Symbol As
Atomic Number 33
Pronunciation /ˈɑrsənɪk/ ar-sə-nik, also /ɑrˈsɛnɪk/ ar-sen-ik when attributive
Element Category metalloid
Group 15
Period 4
Block p
Atomic Weight 74.92160(2)
Electron Configuration [Ar] 4s2 3d10 4p3
Electrons Per Shell 2, 8, 18, 5
Atomic Properties
Oxidation States 5, 3, 2, 1, -3 (mildly acidic oxide)
Electronegativity 2.18 (Pauling scale)
Ionization Energies 1st: 947.0 kJ·mol−1
2nd: 1798 kJ·mol−1
3rd: 2735 kJ·mol−1
Atomic Radius 119 pm
Covalent Radius 119±4 pm
Van der Waals Radius 185 pm
Miscellanea
Crystal Structure trigonal
Magnetic Ordering diamagnetic
Electrical Resistivity (20 °C) 333 nΩ·m
Thermal Conductivity 50.2 W·m−1·K−1
Young's Modulus 8 GPa
Bulk Modulus 22 GPa
Mohs Hardness 3.5
Brinell Hardness 1440 MPa
CAS Registry Number 7440-56-4
Physical Properties
Phase Solid
Density (near r.t.) 5.727 g·cm−3
Liquid Density at m.p. 5.22 g·cm−3
Sublimation Point 887 K, 615 °C, 1137 °F
Triple Point 1090 K (817°C), 3628 kPa
Critical Point 1673 K, ? MPa
Heat of Fusion 34.76 kJ·mol−1
Heat of Vaporization 34.76 kJ·mol−1
Molar Heat Capacity 24.64 J·mol−1·K−1
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
73As syn 80.3 d ε - 73Ge
γ 0.05D, 0.01D, e -
74As syn 17.78 d ε - 74Ge
β+ 0.941 74
γ 0.595, 0.634 -
β− 1.35, 0.717
74Se 100% 75As is stable with 42 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 553 596 646 706 781 874
As
General Properties
Name Selenium
Symbol Se
Atomic Number 34
Pronunciation /sɨˈliːniəm/ si-lee-nee-əm
Element Category nonmetal
Group 16
Period 4
Block p
Atomic Weight 78.96
Electron Configuration [Ar] 4s2 3d10 4p4
Electrons Per Shell 2, 8, 18, 6
Atomic Properties
Oxidation States 6, 4, 2, 1, -2 (strongly acidic oxide)
Electronegativity 2.55 (Pauling scale)
Ionization Energies 1st: 941.0 kJ·mol−1
2nd: 2045 kJ·mol−1
3rd: 2973.7 kJ·mol−1
Atomic Radius 120 pm
Covalent Radius 120±4 pm
Van der Waals Radius 190 pm
Miscellanea
Crystal Structure hexagonal
Magnetic Ordering diamagnetic
Thermal Conductivity (amorphous) 0.519 W·m−1·K−1
Thermal Expansion (25 °C) (amorphous) 37 µm·m−1·K−1
Speed of sound (thin rod) (20 °C) 3350 m·s
Young's Modulus 10 GPa
Shear Modulus 3.7 GPa
Bulk Modulus 8.3 GPa
Poisson Ratio 0.33
Mohs Hardness 2.0
Brinell Hardness 736 MPa
CAS Registry Number 7782-49-2
Physical Properties
Phase solid
Density (near r.t.) (gray) 4.81 g·cm−3
Density (near r.t.) (alpha) 4.39 g·cm−3
Density (near r.t.) (vitreous) 4.28 g·cm−3
Liquid Density at m.p. 3.99 g·cm−3
Melting Point 494 K,221 °C,430 °F
Boiling Point 958 K,685 °C,1265 °F
Critical Point 1766 K, 27.2 MPa
Heat of Fusion (gray) 6.69 kJ·mol−1
Heat of Vaporization 95.48 kJ·mol−1
Molar Heat Capacity 25.363 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
72Se syn 8.4 d ε - 72As
γ 0.046 -
74Se 0.87% 74Se is stable with 40 neutrons
75Se syn 119.779 d ε - 75As
γ 0.264, -
0.136
0.279
76Se 9.36% 76Se is stable with 42 neutrons
77Se 7.63% 77Se is stable with 43 neutrons
78Se 23.78% 78Se is stable with 44 neutrons
79Se trace 3.27*105 y β− 0.151 79Br
80Se 49.61% 80Se is stable with 46 neutrons
82Se 8.73% 1.08*1020 y β−β− 2.995 82Kr
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 500 552 617 704 813 958
Se
General Properties
Name Bromine
Symbol Br
Atomic Number 35
Pronunciation /ˈbroʊmiːn/ broh-meen or /ˈbroʊmɨn/ broh-min
Element Category Halogen
Group 17
Period 4
Block p
Atomic Weight 79.904(1)
Electron Configuration [Ar] 4s2 3d10 4p5
Electrons Per Shell 2, 8, 18, 7
Atomic Properties
Oxidation States 7, 5, 4, 3, 1, -1 (strongly acidic oxide)
Electronegativity 2.96 (Pauling Scale)
Ionization Energies 1st: 1139.9 kJ·mol−1
2nd: 2103 kJ·mol−1
3rd: 3470 kJ·mol−1
Atomic Radius 120 pm
Covalent Radius 120±3 pm
Van der Waals Radius 185 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 185 201 220 244 276 332
Physical Properties
Phase Liquid
Density (near r.t.) (Br2, liquid) 3.1028 g·cm−3
Melting Point 265.8 K,-7.2 °C,19 °F
Boiling Point 332.0 K,58.8 °C,137.8 °F
Critical Point 588 K, 10.34 MPa
Heat of Fusion (Br2) 10.571 kJ·mol−1
Heat of Vaporization (Br2) 29.96 kJ·mol−1
Molar Heat Capacity (Br2) 75.69 J·mol−1·K−1
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
79Br 50.69% 79Br is stable with 44 neutrons
81Br 49.31% 81Br is stable with 46 neutrons
Miscellanea
Crystal Structure Orthorhombic
Magnetic Ordering Diamagnetic
Electrical Resistivity (20 °C) 7.8*1010Ω·m
Thermal Conductivity 0.122 W·m−1·K−1
Speed of Sound (20°C) 206 m·s
CAS Registry Number 7726-95-6
Br
General Properties
Name Krypton
Symbol Kr
Atomic Number 36
Pronunciation /ˈkrɪptɒn/ krip-ton
Element Category Noble Gases
Group 18
Period 4
Block p
Atomic Weight 83.798
Electron Configuration [Ar] 3d10 4s2 4p6
Electrons Per Shell 2, 8, 18, 8
Atomic Properties
Oxidation States 2
Electronegativity 3.00 (Pauling Scale)
Ionization Energies 1st: 1350.8 kJ·mol−1
2nd: 2350.4 kJ·mol−1
3rd: 3470 kJ·mol−1
Covalent Radius 116±4 pm
Van der Waals Radius 202 pm
Miscellanea
Crystal Structure Cubic Face-Centered
Magnetic Ordering Diamagnetic
Thermal Conductivity 9.43x10-3 W·m−1·K−1
Speed of Sound (gas, 23 °C) 220, (liquid) 1120 m·s
CAS Registry Number 7439-90-9
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 59 65 74 120
Physical Properties
Phase Gas
Density (0 °C, 101.325 kPa) 3.749 g/L
Liquid Density at b.p. 2.413 g·cm−3
Melting Point 115.79 K,-157.36 °C,-251.25 °F
Boiling Point 119.93 K,-153.22 °C,-244.12 °F
Triple Point 115.775 K (-157°C), 73.2 kPa
Critical Point 209.41 K, 5.50 MPa
Heat of Fusion 1.64 kJ·mol−1
Heat of Vaporization 9.08 kJ·mol−1
Molar Heat Capacity 5R/2 = 20.786 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
78Kr 0.35% 78Kr is stable with 42 neutrons
79Kr syn 35.04 h ε - 79Br
β+ 0.604 79Br
γ 0.26, 0.39, 0.60 -
80Kr 2.25% 80Kr is stable with 44 neutrons
81Kr Trace 2.29*105 y ε - 81Br
γ 0.281
82Kr 11.6% 82Kr is stable with 46 neutrons
83Kr 11.5% 83Kr is stable with 47 neutrons
84Kr 57% 84Kr is stable with 48 neutrons
85Kr syn 10.756 y β− 0.687 85Rb
86Kr 17.3% 86Kr is stable with 50 neutrons
Kr
5
General Properties
Name Rubidium
Symbol Rb
Atomic Number 37
Pronunciation /rʉˈbɪdiəm/ roo-bid-ee-əm
Element Category Alkali Metal
Group 1
Period 5
Block s
Atomic Weight 85.4678(3)
Electron Configuration [Kr] 5s1
Electrons Per Shell 2, 8, 18, 8, 1
Atomic Properties
Oxidation States 1 (Strongly Basic Oxide)
Electronegativity 0.82 (Pauling Scale)
Ionization Energies 1st: 403 kJ·mol−1
2nd: 2632.1 kJ·mol−1
3rd: 3859.4 kJ·mol−1
Atomic Radius 248 pm
Covalent Radius 220±9 pm
Van der Waals Radius 303 pm
Miscellanea
Crystal Structure Body-Centered Cubic
Magnetic Ordering Paramagnetic
Electrical Resistivity (20 °C) 128 nΩ·m
Thermal Conductivity 58.2 W·m−1·K−1
Speed of Sound (thin rod) (20 °C) 1300 m·s
Young's Modulus 2.4 GPa
Bulk Modulus 2.5 GPa
Mohs Hardness 0.3
Brinell Hardness 0.216 MPa
CAS Registry Number 7440-17-7
Physical Properties
Phase Solid
Density (near r.t.) 1.532 g·cm−3
Liquid Density at m.p. 1.46 g·cm−3
Melting Point 312.46 K,39.31 °C,102.76 °F
Boiling Point 961 K,688 °C,1270 °F
Critical Point (Extrapolated) 2093 K, 16 MPa
Heat of Fusion 2.19 kJ·mol−1
Heat of Vaporization 75.77 kJ·mol−1
Molar Heat Capacity 31.060 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
83Rb syn 86.2 d ε - 83Kr
γ 0.52, -
0.53,
0.55
84Rb syn 32.9 d ε - 84Kr
β+ 1.66, 0.78 84Kr
γ 0.881 -
β− 0.892 84Sr
85Rb 72.168% 85Rb is stable with 48 neutrons
86Rb syn 18.65 d β− 1.775 86Sr
γ 1.0767 -
87Rb 27.835% 4.88*1010 y β− 0.283 87Sr
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 434 486 552 641 769 958
Rb
General Properties
Name Strontium
Symbol Sr
Atomic Number 38
Pronunciation /ˈstrɒnʃiəm/ stron-shee-əm; /ˈstrɒntiəm/ stron-tee-əm; /ˈstrɒnʃəm/ stron-shəm
Element Category Alkaline Earth Metal
Group 2
Period 5
Block s
Atomic Weight 87.62
Electron Configuration [Kr] 5s2
Electrons Per Shell 2, 8, 18, 8, 2
Atomic Properties
Oxidation States 2, 1 (strongly basic oxide)
Electronegativity 0.95 (Pauling Scale)
Ionization Energies 1st: 549.5 kJ·mol−1
2nd: 1064.2 kJ·mol−1
3rd: 4138 kJ·mol−1
Atomic Radius 215 pm
Covalent Radius 195±10 pm
Van der Waals Radius 249 pm
Miscellanea
Crystal Structure Face-Centered Cubic
Magnetic Ordering Paramagnetic
Electrical Resistivity (20 °C) 132 nΩ·m
Thermal Conductivity 35.4 W·m−1·K−1
Thermal Expansion (25 °C) 22.5 µm·m−1·K−1
Shear Modulus 6.1 GPa
Poisson Ratio 0.28
Mohs Hardness 1.5
CAS Registry Number 7440-24-6
Physical Properties
Phase Solid
Density (near r.t.) 2.64 g·cm−3
Liquid Density at m.p. 2.375 g·cm−3
Melting Point 1050 K,777 °C,1431 °F
Boiling Point 1655 K,1382 °C,2520 °F
Heat of Fusion 7.43 kJ·mol−1
Heat of Vaporization 136.9 kJ·mol−1
Molar Heat Capacity 26.4 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
82Sr syn 25.36 d ε - 82Rb
83Sr syn 1.35 d ε - 83Rb
β+ 1.23 83Rb
γ 0.76, 0.36 -
84Sr 0.56% 84Sr is stable with 46 neutrons
85Sr syn 64.84 d ε - 85Rb
γ 0.514D -
86Sr 9.86% 86Sr is stable with 48 neutrons
87Sr 7.0% 87Sr is stable with 49 neutrons
88Sr 82.58% 88Sr is stable with 50 neutrons
89Sr Syn 50.52 d ε 1.49 89Rb
β− 0.909D 89Y
90Sr Trace 28.90 y β− 0.546 90Y
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 796 882 990 1139 1345 1646
Sr
General Properties
Name Yttrium
Symbol Y
Atomic Number 39
Pronunciation /ˈɪtriəm/ it-ree-əm
Element Category Transition Metal
Group 3
Period 5
Block d
Atomic Weight 88.90585
Electron Configuration [Kr] 4d1 5s2
Electrons Per Shell 2, 8, 18, 9, 2
Atomic Properties
Oxidation States 3, 2, 1 (Weakly Basic Oxide)
Electronegativity 1.22 (Pauling Scale)
Ionization Energies 1st: 600 kJ·mol−1
2nd: 1180 kJ·mol−1
3rd: 1980 kJ·mol−1
Atomic Radius 180 pm
Covalent Radius 190±7 pm
Miscellanea
Crystal Structure Hexagonal
Magnetic Ordering Paramagnetic
Electrical Resistivity (r.t.) (α, poly) 596 nΩ·m
Thermal Conductivity 17.2 W·m−1·K−1
Thermal Expansion (r.t.) (α, poly) 10.6 µm/(m·K)
Speed of sound (thin rod) (20 °C) 3300 m·s-1
Young's Modulus 63.5 GPa
Shear Modulus 25.6 GPa
Bulk Modulus 41.2 GPa
Poisson Ratio 0.243
Brinell Hardness 589 MPa
CAS Registry Number 7440-65-5
Physical Properties
Phase Solid
Density (near r.t.) 4.472 g·cm−3
Liquid Density at m.p. 4.24 g·cm−3
Melting Point 1799 K,1526 °C,2779 °F
Boiling Point 3609 K,3336 °C,6037 °F
Heat of Fusion 11.42 kJ·mol−1
Heat of Vaporization 365 kJ·mol−1
Molar Heat Capacity 26.53 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
87 Y Syn 3.35 d ε - 87Sr
γ 0.48, 0.38D -
88Y Syn 106.6 d ε - 88Sr
γ 1.83, 0.89 -
89Y 100% 89Y is stable with 50 neutrons
90Y Syn 2.67 d β− 2.28 90Zr
γ 2.18 -
91Y Syn 58.5 d β− 1.54 91Zr
γ 1.20 -
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1883 2075 (2320) (2627) (3036) (3607)
Y
General Properties
Name Zirconium
Symbol Zr
Atomic Number 40
Pronunciation /zərˈkoʊniəm/ zər-koh-ni-əm
Element Category Transition Metal
Group 4
Period 5
Block d
Atomic Weight 91.224
Electron Configuration [Kr] 5s2 4d2
Electrons Per Shell 2, 8, 18, 10, 2
Atomic Properties
Oxidation States 4, 3, 2, 1, (amphoteric oxide)
Electronegativity 1.33 (Pauling Scale)
Ionization Energies 1st: 640.1 kJ·mol−1
2nd: 1270 kJ·mol−1
3rd: 2218 kJ·mol−1
Atomic Radius 160 pm
Covalent Radius 175±7 pm
Miscellanea
Crystal Structure Hexagonal Close-Packed
Magnetic Ordering Paramagnetic
Electrical Resistivity (20 °C) 421 nΩ·m
Thermal Conductivity 22.6 W·m−1·K−1
Thermal Expansion (25 °C) 5.7 µm·m−1·K−1
Speed of Sound (thin rod) (20 °C) 3800 m·s
Young's Modulus 88 GPa
Shear Modulus 33 GPa
Bulk Modulus 91.1 GPa
Poisson Ratio 0.34
Mohs Hardness 5.0
Vickers Hardness 903 MPa
CAS Registry Number 7440-67-7
Physical Properties
Phase Solid
Density (near r.t.) 6.52 g·cm−3
Liquid Density at m.p. 5.8 g·cm−3
Melting Point 2128 K,1855 °C,3371 °F
Boiling Point 4682 K,4409 °C,7968 °F
Heat of Fusion 14 kJ·mol−1
Heat of Vaporization 573 kJ·mol−1
Molar Heat Capacity 25.36 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
88Zr Syn 83.4 d ε - 88Y
γ 0.392D -
89Zr Syn 78.4 h ε - 89Y
β+ 0.902 89Y
γ 0.909D -
90Zr 51.45% 90Zr is stable with 50 neutrons
91Zr 11.22% 91Zr is stable with 51 neutrons
92Zr 17.15% 92Zr is stable with 52 neutrons
93Zr Trace 1.53*106 y β− 0.060 93Nb
94Zr 17.38% >1.1*1017 y β−β− 1.144 94Mo
96Zr 2.8% 2.0*1019 y β−β− 3.348 96Mo
Zr
General Properties
Name Niobium
Symbol Nb
Atomic Number 41
Pronunciation /naɪˈoʊbiəm/ nye-oh-bee-əm; alternatively, /kəˈlʌmbiəm/ kə-lum-bee-əm
Element Category Transition Metal
Group 5
Period 5
Block d
Atomic Weight 92.90638
Electron Configuration [Kr] 4d4 5s1
Electrons Per Shell 2, 8, 18, 12, 1
Atomic Properties
Oxidation States 5, 4, 3, 2, -1 (Mildly Acidic Oxide)
Electronegativity 1.6 (Pauling Scale)
Ionization Energies 1st: 652.1 kJ·mol−1
2nd: 1380 kJ·mol−1
3rd: 2416 kJ·mol−1
Atomic Radius 146 pm
Covalent Radius 164±6 pm
Miscellanea
Crystal Structure Cubic Body-Centered
Magnetic Ordering Paramagnetic
Electrical Resistivity (0 °C) 152 nΩ·m
Thermal Conductivity 53.7 W·m−1·K−1
Thermal Expansion 7.3 µm/(m·K)
Speed of Sound (thin rod) (20 °C) 3800 m·s
Young's Modulus 105 GPa
Shear Modulus 38 GPa
Bulk Modulus 170 GPa
Poisson Ratio 0.40
Mohs Hardness 6.0
Vickers Hardness 1320 MPa
Brinell Hardness 736 MPa
CAS Registry Number 7440-03-1
Physical Properties
Phase Solid
Density (near r.t.) 8.57 g·cm−3
Melting Point 2750 K,2477 °C,4491 °F
Boiling Point 5017 K,4744 °C,8571 °F
Heat of Fusion 30 kJ·mol−1
Heat of Vaporization 689.9 kJ·mol−1
Molar Heat Capacity 24.60 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
91Nb Syn 6.8*102 y ε - 91Zr
91mNb Syn 60.86 d IT 0.104e 91Nb
92Nb Syn 10.15 d ε - 92Zr
γ 0.934 -
92Nb Syn 3.47*107y ε - 92Zr
γ 0.561, 0.934 -
93Nb 100% 93Nb is stable with 52 neutrons
93mNb Syn 16.13 y IT 0.031e 93Nb
94Nb Syn 2.03*104 y β− 0.471 94Mo
γ 0.702, 0.871 -
95Nb Syn 34.991 d β− 0.159 95Mo
γ 0.765 -
95mNb syn 3.61 d IT 0.235 95Nb
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 2942 3207 3524 3910 4393 5013
Nb
General Properties
Name Molybdenum
Symbol Mo
Atomic Number 42
Pronunciation /ˌmɒlɪbˈdiːnəm/ mol-ib-dee-nəm or /məˈlɪbdɨnəm/ mə-lib-di-nəm
Element Category Transition Metal
Group 6
Period 5
Block d
Atomic Weight 95.94(1)
Electron Configuration [Kr] 5s1 4d5
Electrons Per Shell 2, 8, 18, 13, 1
Atomic Properties
Oxidation States 6, 5, 4, 3, 2, 1, -1, -2 (Strongly Acidic Oxide)
Electronegativity 2.16 (Pauling Scale)
Ionization Energies 1st: 684.3 kJ·mol−1
2nd: 1560 kJ·mol−1
3rd: 2618 kJ·mol−1
Atomic Radius 139 pm
Covalent Radius 154±5 pm
Van der Waals Radius
Miscellanea
Crystal Structure Body-Centered Cubic
Magnetic Ordering Paramagnetic
Electrical Resistivity (20 °C) 53.4 nΩ·m
Thermal Conductivity 138 W·m−1·K−1
Thermal Expansion (25 °C) 4.8 µm·m−1·K−1
Young's Modulus 329 GPa
Shear Modulus 126 GPa
Bulk Modulus 230 GPa
Poisson Ratio 0.31
Mohs Hardness 5.5
Vickers Hardness 1530 MPa
Brinell Hardness 1500 MPa
CAS Registry Number 7439-98-7
Physical Properties
Phase Solid
Density (near r.t.) 10.28 g·cm−3
Liquid Density at m.p. 9.33 g·cm−3
Melting Point 2896 K,2623 °C,4753 °F
Boiling Point 4912 K,4639 °C,8382 °F
Heat of Fusion 37.48 kJ·mol−1
Heat of Vaporization 598 kJ·mol−1
Molar Heat Capacity 24.06 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
92Mo 14.84% 92Mo is stable with 50 neutrons
93Mo Syn 4*103 y ε - 93Nb
94Mo 9.25% 94Mo is stable with 52 neutrons
95Mo 15.92% 95Mo is stable with 53 neutrons
96Mo 16.68% 96Mo is stable with 54 neutrons
97Mo 9.55% 97Mo is stable with 55 neutrons
98Mo 24.13% 98Mo is stable with 56 neutrons
99Mo Syn 65.94 h β− 0.436, 99mTc
1.214
γ 0.74, -
0.36,
0.14
100Mo 9.63% 7.8*1018 y β−β− 3.04 100Ru
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 2742 2994 3312 3707 4212 4879
Mo
General Properties
Name Technetium
Symbol Tc
Atomic Number 43
Pronunciation /tɛkˈniːʃiəm/ tek-nee-shee-əm
Element Category Transition Metal
Group 7
Period 5
Block d
Atomic Weight 98(0)
Electron Configuration [Kr] 4d5 5s2
Electrons Per Shell 2, 8, 18, 13, 2
Atomic Properties
Oxidation States 7, 6, 5, 4, 3, 2, 1, -1, -3 (Strongly Acidic Oxide)
Electronegativity 1.9 (Pauling Scale)
Ionization Energies 1st: 702 kJ·mol−1
2nd: 1470 kJ·mol−1
3rd: 2850 kJ·mol−1
Atomic Radius 136 pm
Covalent Radius 147±7 pm
Van der Waals Radius
Miscellanea
Crystal Structure Hexagonal
Magnetic Ordering Paramagnetic
Thermal Conductivity 50.6 W·m−1·K−1
Speed of Sound (thin rod) (20 °C) 16,200 m·s
CAS Registry Number 7440-26-8
Vapour Pressure Extrapolated
P (Pa) 1 10 100 1K 1OK 100K
at T (K) 2727 2998 3324 3726 4234 4894
Physical Properties
Phase Solid
Density (near r.t.) 11 g·cm−3
Melting Point 2430 K,2157 °C,3915 °F
Boiling Point 4538 K,4265 °C,7709 °F
Heat of Fusion 33.29 kJ·mol−1
Heat of Vaporization 33.29 kJ·mol−1
Molar Heat Capacity 24.27 J·mol·K
Most Stable Isotopes
Iso NA Half Life DM DE (MeV) DP
95mTc Syn 61 d ε - 95Mo
γ 0.204, -
0.582,
0.835
IT 0.0389, e 95Tc
96Tc Syn 4.3 d ε - 96Mo
γ 0.778, -
0.849,
0.812
97Tc Syn 2.6*106 y ε - 97Mo
97mTc Syn 91 d IT 0.965, e 97Tc
98Tc Syn 4.2*106 y β− 0.4 98Ru
γ 0.745, 0.652 -
99Tc Trace 2.111*105 y β− 0.294 99Ru
99mTc Syn 6.01 h IT 0.142, 0.002 99Tc
γ 0.140 -
Tc
General Properties
Name Ruthenium
Symbol Ru
Atomic Number 44
Pronunciation /ruːˈθiːniəm/ roo-thee-nee-əm
Element Category Transition Metal
Group 8
Period 5
Block d
Atomic Weight 101.07
Electron Configuration [Kr] 4d7 5s1
Electrons Per Shell 2, 8, 18, 15, 1
Atomic Properties
Oxidation States 8, 7, 6, 4, 3, 2, 1,[1], -2 (Mildly Acidic Oxide)
Electronegativity 2.2 (Pauling Scale)
Ionization Energies 1st: 710.2 kJ·mol−1
2nd: 1620 kJ·mol−1
3rd: 2747 kJ·mol−1
Atomic Radius 134 pm
Covalent Radius 146±7 pm
Miscellanea
Crystal Structure Hexagonal
Magnetic Ordering Paramagnetic
Electrical Resistivity (0 °C) 71 nΩ·m
Thermal Conductivity 117 W·m−1·K−1
Thermal Expansion (25 °C) 6.4 µm·m−1·K−1
Speed of Sound (thin rod) (20 °C) 5970 m·s
Young's Modulus 447 GPa
Shear Modulus 173 GPa
Bulk Modulus 220 GPa
Poisson Ratio 0.30
Mohs Hardness 6.5
Brinell Hardness 2160 MPa
CAS Registry Number 7440-18-8
Physical Properties
Density (near r.t.) 12.45 g·cm−3
Liquid Density at m.p. 10.65 g·cm−3
Melting Point 2607 K,2334 °C,4233 °F
Boiling Point 4423 K,4150 °C,7502 °F
Heat of Fusion 38.59 kJ·mol−1
Heat of Vaporization 591.6 kJ·mol−1
Molar Heat Capacity 24.06 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
96Ru 5.52% 96Ru is stable with 52 neutrons
97Ru Syn 2.9 d ε - 97Tc
γ 0.215, 0.324 -
98Ru 1.88% 98Ru is stable with 54 neutrons
99Ru 12.7% 99Ru is stable with 55 neutrons
100Ru 12.6% 100Ru is stable with 56 neutrons
101Ru 17.0% 101Ru is stable with 57 neutrons
102Ru 31.6% 102Ru is stable with 58 neutrons
103Ru Syn 39.26 d β− 0.226 103Rh
γ 0.497 -
104Ru 18.7% 104Ru is stable with 60 neutrons
106Ru Syn 373.59 d β− 3.54 106Rh
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 2588 2811 3087 3424 3845 4388
Ru
General Properties
Name Rhodium
Symbol Rh
Atomic Number 45
Pronunciation /ˈroʊdiəm/ roh-dee-əm
Element Category Transition Metal
Group 9
Period 5
Block d
Atomic Weight 102.90550
Electron Configuration [Kr] 5s1 4d8
Electrons Per Shell 2, 8, 18, 16, 1
Atomic Properties
Oxidation States 6, 5, 4, 3, 2, 1, -1 (Amphoteric Oxide)
Electronegativity 2.28 (Pauling Scale)
Ionization Energies 1st: 719.7 kJ·mol−1
2nd: 1740 kJ·mol−1
3rd: 2997 kJ·mol−1
Atomic Radius 134 pm
Covalent Radius 142±7 pm
Miscellanea
Crystal Structure Face-Centered Cubic
Magnetic Ordering Paramagnetic
Electrical Resistivity (0 °C) 43.3 nΩ·m
Thermal Conductivity 150 W·m−1·K−1
Thermal Expansion (25 °C) 8.2 µm·m−1·K−1
Speed of Sound (thin rod) (20 °C) 4700 m·s
Young's Modulus 380 GPa
Shear Modulus 150 GPa
Bulk Modulus 275 GPa
Poisson Ratio 0.26
Mohs Hardness 6.0
Vickers Hardness 1246 MPa
Brinell Hardness 1100 MPa
CAS Registry Number 7440-16-6
Physical Properties
Phase Solid
Density (near r.t.) 12.41 g·cm−3
Liquid Density at m.p. 10.7 g·cm−3
Melting Point 2237 K,1964 °C,3567 °F
Boiling Point 3968 K,3695 °C,6683 °F
Heat of Fusion 26.59 kJ·mol−1
Heat of Vaporization 494 kJ·mol−1
Molar Heat Capacity 24.98 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
99Rh Syn 16.1 d ε - 99Ru
γ 0.089, 0.353, -
0.528
101mRh Syn 4.34 d ε - 101Ru
IT 0.157 101Rh
γ 0.306, 0.545 -
101Rh Syn 3.3 y ε - 101Ru
γ 0.127, 0.198, -
0.325
102mRh Syn 2.9 y ε - 102Ru
γ 0.475, 0.631, -
0.697, 1.046
102Rh Syn 207 d ε - 102Ru
β+ 0.826, 1.301 102Ru
− 1.151 102Pd
γ 0.475, 0.628 -
103Rh 100% 103Rh is stable with 58 neutrons
105Rh Syn 35.36 h β− 0.247, 0.260, 105Pd
0.566
γ 0.306, 0.318 -
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 2288 2496 2749 3063 3405 3997
Rh
General Properties
Name Palladium
Symbol Pd
Atomic Number 46
Pronunciation /pəˈleɪdiəm/ pə-lay-dee-əm
Element Category Transition Metal
Group 10
Period 5
Block d
Atomic Weight 106.42
Electron Configuration [Kr] 4d10
Electrons Per Shell 2, 8, 18, 18
Atomic Properties
Oxidation States 0, +1, +2, +4, +6 (Mildly Basic Oxide)
Electronegativity 2.20 (Pauling Scale)
Ionization Energies 1st: 804.4 kJ·mol−1
2nd: 1870 kJ·mol−1
3rd: 3177 kJ·mol−1
Atomic Radius 137 pm
Covalent Radius 139±6 pm
Van der Waals Radius 163 pm
Miscellanea
Crystal Structure Face-Centered Cubic
Magnetic Ordering Paramagnetic
Electrical Resistivity (20 °C) 105.4 nΩ·m
Thermal Conductivity 71.8 W·m−1·K−1
Thermal Expansion (25 °C) 11.8 µm·m−1·K−1
Speed of Sound (thin rod) (20 °C) 3070 m·s
Young's Modulus 121 GPa
Shear Modulus 44 GPa
Bulk Modulus 180 GPa
Poisson Ratio 0.39
Mohs Hardness 4.75
Vickers Hardness 461 MPa
Brinell Hardness 37.3 MPa
CAS Registry Number 7440-05-3
Physical Properties
Phase Solid
Density (near r.t.) 12.023 g·cm−3
Liquid Density at m.p. 10.38 g·cm−3
Melting Point 1828.05 K,1554.9 °C,2830.82 °F
Boiling Point 3236 K,2963 °C,5365 °F
Heat of Fusion 16.74 kJ·mol−1
Heat of Vaporization 362 kJ·mol−1
Molar Heat Capacity 25.98 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
100Pd Syn 3.63 d ε - 100Rh
γ 0.084, -
0.074,
0.126
102Pd 1.02% 102Pd is stable with 56 neutrons
103Pd Syn 16.991 d ε - 103Rh
104Pd 11.14% 104Pd is stable with 58 neutrons
105Pd 22.33% 105Pd is stable with 59 neutrons
106Pd 27.33% 106Pd is stable with 60 neutrons
107Pd Trace 6.5*106 y β− 0.033 107Ag
108Pd 26.46% 108Pd is stable with 62 neutrons
110Pd 11.72% 110Pd is stable with 64 neutrons
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1721 1897 2117 2395 2753 3234
Pd
General Properties
Name Silver
Symbol Ag
Atomic Number 47
Pronunciation /ˈsɪlvər/
Element Category Transition Metal
Group 11
Period 5
Block d
Atomic Weight 107.8682
Electron Configuration [Kr] 4d10 5s1
Electrons Per Shell 2, 8, 18, 18, 1
Atomic Properties
Oxidation States 1, 2, 3 (Amphoteric Oxide)
Electronegativity 1.93 (Pauling Scale)
Ionization Energies 1st: 731.0 kJ·mol−1
2nd: 2070 kJ·mol−1
3rd: 3361 kJ·mol−1
Atomic Radius 144 pm
Covalent Radius 145±5 pm
Van der Waals Radius 172 pm
Miscellanea
Crystal Structure Face-Centered Cubic
Magnetic Ordering Diamagnetic
Electrical Resistivity (20 °C) 15.87 nΩ·m
Thermal Conductivity 429 W·m−1·K−1
Thermal Diffusivity (300 K) 174 mm²/s
Thermal Expansion (25 °C) 18.9 µm·m−1·K−1
Young's Modulus 83 GPa
Shear Modulus 30 GPa
Bulk Modulus 100 GPa
Poisson Ratio 0.37
Mohs Hardness 2.5
Vickers Hardness 251 MPa
Brinell Hardness 24.5 MPa
CAS Registry Number 7440-22-4
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1283 1413 1575 1782 2055 2433
Physical Properties
Phase Solid
Density (near r.t.) 10.49 g·cm−3
Liquid Density at m.p. 9.320 g·cm−3
Melting Point 1234.93 K,961.78 °C,1763.2 °F
Boiling Point 2435 K,2162 °C,3924 °F
Heat of Fusion 11.28 kJ·mol−1
Heat of Vaporization 250.58 kJ·mol−1
Molar Heat Capacity 25.350 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
105Ag Syn 41.2 d ε - 105Pd
γ 0.344, -
0.280,
0.644,
0.443
106mAg Syn 8.28 d ε - 106Pd
γ 0.511, -
0.717,
1.045,
0.450
107Ag 51.839% 107Ag is stable with 60 neutrons
108mAg Syn 418 y ε - 108Pd
IT 0.109 108Ag
γ 0.433, -
0.614,
0.722
109Ag 48.161% 109Ag is stable with 62 neutrons
111Ag Syn 7.45 d β− 1.036, 111Cd
0.694
γ 0.342 -
Ag
General Properties
Name Cadmium
Symbol Cd
Atomic Number 48
Pronunciation /ˈkædmiəm/ kad-mee-əm
Element Category Transition Metal
Group 12
Period 5
Block d
Atomic Weight 112.411
Electron Configuration [Kr] 5s2 4d10
Electrons Per Shell 2, 8, 18, 18, 2
Atomic Properties
Oxidation States 2, 1 (Mildly Basic Oxide)
Electronegativity 1.69 (Pauling Scale)
Ionization Energies 1st: 867.8 kJ·mol−1
2nd: 1631.4 kJ·mol−1
3rd: 3616 kJ·mol−1
Atomic Radius 151 pm
Covalent Radius 144±9 pm
Van der Waals Radius 158 pm
Miscellanea
Crystal Structure Hexagonal
Magnetic Ordering Diamagnetic
Electrical Resistivity (22 °C) 72.7 nΩ·m
Thermal Conductivity 96.6 W·m−1·K−1
Thermal Expansion (25 °C) 30.8 µm·m−1·K−1
Speed of Sound (thin rod) (20 °C) 2310 m·s
Young's Modulus 50 GPa
Shear Modulus 19 GPa
Bulk Modulus 42 GPa
Poisson Ratio 0.30
Mohs Hardness 2.0
Brinell Hardness 203 MPa
CAS Registry Number 7440-43-9
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 530 583 654 745 867 1040
Physical Properties
Phase Solid
Density (near r.t.) 8.65 g·cm−3
Liquid Density at m.p. 7.996 g·cm−3
Melting Point 594.22 K,321.07 °C,609.93 °F
Boiling Point 1040 K,767 °C,1413 °F
Heat of Fusion 6.21 kJ·mol−1
Heat of Vaporization 99.87 kJ·mol−1
Molar Heat Capacity 26.020 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
106Cd 1.25% >9.5*1017 y εε2ν - 106Pd
107Cd Syn 6.5 h ε 1.417 107Ag
108Cd 0.89% >6.7*1017 y εε2ν - 108Pd
109Cd Syn 462.6 d ε 0.214 109Ag
110Cd 12.49% 110Cd is stable with 62 neutrons
111Cd 12.8% 111Cd is stable with 63 neutrons
112Cd 24.13% 112Cd is stable with 64 neutrons
113Cd 12.22% 7.7*1015 y β− 0.316 113In
113mCd Syn 14.1 y β− 0.580 113In
IT 0.264 113Cd
113Cd 28.73% >9.3*1017 y ββ2ν - 114Sn
115Cd Syn 53.46 h β− 1.446 115In
116Cd 7.49% 2.9*1019 y ββ2ν - 116Sn
Cd
General Properties
Name Indium
Symbol In
Atomic Number 49
Pronunciation /ˈɪndiəm/ in-dee-əm
Element Category Post-Transition Metal
Group 13
Period 5
Block p
Atomic Weight 114.818
Electron Configuration [Kr] 4d10 5s2 5p1
Electrons Per Shell 2, 8, 18, 18, 3
Atomic Properties
Oxidation States 3, 2, 1 (Amphoteric Oxide)
Electronegativity 1.78 (Pauling Scale)
Ionization Energies 1st: 558.3 kJ·mol−1
2nd: 1820.7 kJ·mol−1
3rd: 2704 kJ·mol−1
Atomic Radius 167 pm
Covalent Radius 142±5 pm
Van der Waals Radius 193 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1196 1325 1485 1690 1962 2340
Physical Properties
Phase Solid
Density (near r.t.) 7.31 g·cm−3
Liquid Density at m.p. 7.02 g·cm−3
Melting Point 429.7485 K,156.5985 °C,313.8773 °F
Boiling Point 2345 K,2072 °C,3762 °F
Heat of Fusion 3.281 kJ·mol−1
Heat of Vaporization 231.8 kJ·mol−1
Molar Heat Capacity 26.74 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
113In 4.3% 113In is stable with 64 neutrons
115In 95.7% 4.41*1014 y β− 0.495 115Sn
Miscellanea
Crystal Structure Tetragonal
Magnetic Ordering Diamagnetic
Electrical Resistivity (20 °C) 83.7 nΩ·m
Thermal Conductivity 81.8 W·m−1·K−1
Thermal Expansion (25 °C) 18.9 µm·m−1·K−1
Speed of Sound (thin rod) (20 °C) 1215 m·s
Young's Modulus 11 GPa
Mohs Hardness 1.2
Brinell Hardness 8.83 MPa
CAS Registry Number 7440-74-6
In
General Properties
Name Tin
Symbol Sn
Atomic Number 50
Pronunciation /ˈtɪn/
Element Category Post-Transition Metal
Group 14
Period 5
Block p
Atomic Weight 118.710
Electron Configuration [Kr] 4d10 5s2 5p2
Electrons Per Shell 2, 8, 18, 18, 4
Atomic Properties
Oxidation States 4, 2, -4 (Amphoteric Oxide)
Electronegativity 1.96 (Pauling Scale)
Ionization Energies 1st: 708.6 kJ·mol−1
2nd: 1411.8 kJ·mol−1
3rd: 2943.0 kJ·mol−1
Atomic Radius 140 pm
Covalent Radius 139±4 pm
Van der Waals Radius 217 pm
Miscellanea
Crystal Structure Tetragonal (white), Diamond Cubic (gray)
Magnetic Ordering (gray)Diamagnetic, (white) Paramagnetic
Electrical Resistivity (0 °C) 115 nΩ·m
Thermal Conductivity 66.8 W·m−1·K−1
Thermal Expansion (25 °C) 22.0 µm·m−1·K−1
Young's Modulus 50 GPa
Shear Modulus 18 GPa
Bulk Modulus 58 GPa
Poisson Ratio 0.36
Mohs Hardness 1.5
Brinell Hardness 51 MPa
CAS Registry Number 7440-31-5
Physical Properties
Phase Solid
Density (near r.t.) (white) 7.365 g·cm−3
Density (near r.t.) (gray) 5.769 g·cm−3
Liquid Density at m.p. 6.99 g·cm−3
Melting Point 505.08 K,231.93 °C,449.47 °F
Boiling Point 2875 K,2602 °C,4716 °F
Heat of Fusion (white) 7.03 kJ·mol−1
Heat of Vaporization (white) 296.1 kJ·mol−1
Molar Heat Capacity (white) 27.112 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
112Sn 0.97% 112Sn is stable with 62 neutrons
114Sn 0.66% 114Sn is stable with 64 neutrons
115Sn 0.34% 115Sn is stable with 65 neutrons
116Sn 14.54% 116Sn is stable with 66 neutrons
117Sn 7.68% 117Sn is stable with 67 neutrons
118Sn 24.22% 118Sn is stable with 68 neutrons
119Sn 8.59% 119Sn is stable with 69 neutrons
120Sn 32.58% 120Sn is stable with 70 neutrons
122Sn 4.63% 122Sn is stable with 72 neutrons
124Sn 5.79% 124Sn is stable with 74 neutrons
126Sn Trace 2.3*105 y β− 0.380 126Sb
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 1497 1657 1855 2107 2438 2893
Sn
General Properties
Name Antimony
Symbol Sb
Atomic Number 51
Pronunciation /ˈæntɨmɵnɪ/ an-ti-mo-nee
Element Category Metalloid
Group 15
Period 5
Block p
Atomic Weight 121.760(1)
Electron Configuration [Kr] 4d10 5s2 5p3
Electrons Per Shell 2, 8, 18, 18, 5
Atomic Properties
Oxidation States 5, 3, -3
Electronegativity 2.05 (Pauling Scale)
Ionization Energies 1st: 834 kJ·mol−1
2nd: 1594.9 kJ·mol−1
3rd: 2440 kJ·mol−1
Atomic Radius 140 pm
Covalent Radius 139±5 pm
Van der Waals Radius 206 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 807 876 1011 1219 1491 1858
Physical Properties
Phase Solid
Density (near r.t.) 6.697 g·cm−3
Liquid Density at m.p. 6.53 g·cm−3
Melting Point 903.78 K,630.63 °C,1167.13 °F
Boiling Point 1860 K,1587 °C,2889 °F
Heat of Fusion 19.79 kJ·mol−1
Heat of Vaporization 193.43 kJ·mol−1
Molar Heat Capacity 25.23 J·mol−1·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
121Sb 57.36% 121Sb is stable with 70 neutrons
123Sb 42.64% 123Sb is stable with 72 neutrons
125Sb Syn 2.7582 y β− 0.767 125Te
Miscellanea
Crystal Structure Trigonal
Magnetic Ordering Diamagnetic
Electrical Resistivity (20 °C) 417 nΩ·m
Thermal Conductivity 24.4 W·m−1·K−1
Thermal Expansion (25 °C) 11 µm·m−1·K−1
Speed of Sound (thin rod) (20 °C) 3420 m·s
Young's Modulus 55 GPa
Shear Modulus 20 GPa
Bulk Modulus 42 GPa
Mohs Hardness 3.0
Brinell Hardness 294 MPa
CAS Registry Number 7440-36-0
Sb
General Properties
Name Tellurium
Symbol Te
Atomic Number 52
Pronunciation /tɨˈlʊəriəm/, /tɛˈlʊəriəm/ te-loor-ee-əm, or /tɨˈljʊəriəm/ te-lyoor-ee-əm
Element Category Metalloid
Group 16
Period 5
Block p
Atomic Weight 127.60
Electron Configuration [Kr] 4d10 5s2 5p4
Electrons Per Shell 2, 8, 18, 18, 6
Atomic Properties
Oxidation States 6, 5, 4, 2, -2 (Mildly Acidic Oxide)
Electronegativity 2.1 (Pauling Scale)
Ionization Energies 1st: 869.3 kJ·mol−1
2nd: 1790 kJ·mol−1
3rd: 2698 kJ·mol−1
Atomic Radius 140 pm
Covalent Radius 138±4 pm
Van der Waals Radius 206 pm
Miscellanea
Crystal Structure Hexagonal
Magnetic Ordering Diamagnetic
Thermal Conductivity (1.97–3.38) W·m−1·K−1
Speed of Sound (thin rod) (20 °C) 2610 m·s
Young's Modulus 43 GPa
Shear Modulus 16 GPa
Bulk Modulus 65 GPa
Mohs Hardness 2.25
Brinell Hardness 180 MPa
CAS Registry Number 13494-80-9
Physical Properties
Phase Solid
Density (near r.t.) 6.24 g·cm−3
Liquid Density at m.p. 5.70 g·cm−3
Melting Point 722.66 K,449.51 °C,841.12 °F
Boiling Point 1261 K,988 °C,1810 °F
Heat of Fusion 17.49 kJ·mol−1
Heat of Vaporization 114.1 kJ·mol−1
Molar Heat Capacity 25.73 J·mol·K
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
120Te 0.09% >2.2*1016y ε ε 1.701 120Sn
121Te Syn 16.78 d ε 1.040 121Sb
122Te 2.55% 122Te is stable with 70 neutrons
123Te 0.89% >1.0*1013 y ε 0.051 123Sb
124Te 4.74% 124Te is stable with 72 neutrons
125Te 7.07% 125Te is stable with 73 neutrons
126Te 18.84% 126Te is stable with 74 neutrons
127Te Syn 9.35 h β− 0.698 127I
128Te 31.74% 2.2*1024 y β−β− 0.867 128Xe
129Te Syn 69.6 min β− 1.498 129I
130Te 34.08% 7.9*1020 y β−β− 2.528 130Xe
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) (775) (888) 1042 1266
Te
General Properties
Name Iodine
Symbol I
Atomic Number 53
Pronunciation /ˈaɪ.ɵdaɪn/ eye-o-dyne, /ˈaɪ.ɵdɨn/ eye-o-dən, or /ˈaɪ.ɵdiːn/ eye-o-deen
Element Category Halogen
Group 17
Period 5
Block p
Atomic Weight 126.90447
Electron Configuration [Kr] 4d10 5s2 5p5
Electrons Per Shell 2, 8, 18, 18, 7
Atomic Properties
Oxidation States 7, 5, 3, 1, -1 (Strongly Acidic Oxide)
Electronegativity 2.66 (Pauling Scale)
Ionization Energies 1st: 1008.4 kJ·mol−1
2nd: 1845.9 kJ·mol−1
3rd: 3180 kJ·mol−1
Atomic Radius 140 pm
Covalent Radius 139±3 pm
Van der Waals Radius 198 pm
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 260 282 309 342 381 457
Physical Properties
Phase Solid
Density (near r.t.) 4.933 g·cm−3
Melting Point 386.85 K,113.7 °C,236.66 °F
Boiling Point 457.4 K,184.3 °C,363.7 °F
Triple Point 386.65 K (113°C), 12.1 kPa
Critical Point 819 K, 11.7 MPa
Heat of Fusion (I2) 15.52 kJ·mol−1
Heat of Vaporization (I2) 41.57 kJ·mol−1
Molar Heat Capacity (I2) 54.44 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
123I Syn 13 h ε, γ 0.16 123Te
127I 100% 127I is stable with 74 neutrons
129I Trace 15.7*106 y β− 0.194 129Xe
131I Syn 8.02070 d β−, γ 0.971 131Xe
Miscellanea
Crystal Structure Orthorhombic
Magnetic Ordering Diamagnetic
Electrical Resistivity (0 °C) 1.3*107Ω·m
Thermal Conductivity 0.449 W·m−1·K−1
Bulk Modulus 7.7 GPa
CAS Registry Number 7553-56-2
I
General Properties
Name Xenon
Symbol Xe
Atomic Number 54
Pronunciation /ˈzɛnɒn/ zen-on or /ˈziːnɒn/ zee-non
Element Category Noble Gases
Group 18
Period 5
Block p
Atomic Weight 131.293(6)
Electron Configuration [Kr] 5s2 4d10 5p6
Electrons Per Shell 2, 8, 18, 18, 8
Atomic Properties
Oxidation States 0, +1, +2, +4, +6, +8 (rarely more than 0) (weakly acidic oxide)
Electronegativity 2.6 (Pauling Scale)
Ionization Energies 1st: 1170.4 kJ·mol−1
2nd: 2046.4 kJ·mol−1
3rd: 3099.4 kJ·mol−1
Covalent Radius 140±9 pm
Van der Waals Radius 216 pm
Miscellanea
Crystal Structure Face-Centered Cubic
Magnetic Ordering diamagnetic
Thermal Conductivity 5.65*10-3 W·m−1·K−1
Speed of Sound (liquid) 1090 m/s; (gas) 169 m·s
CAS Registry Number 7440-63-3
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
at T (K) 83 92 103 117 137 165
Physical Properties
Phase Gas
Density (0 °C, 101.325 kPa) 5.894 g/L
Liquid Density at b.p. 3.057 g·cm−3
Melting Point (101.325 kPa) 161.4 K,-111.7 °C,-169.1 °F
Boiling Point (101.325 kPa) 165.03 K,-108.12 °C,-162.62 °F
Triple Point 161.405 K (-112°C), 81.6 kPa
Critical Point 289.77 K, 5.841 MPa
Heat of Fusion (101.325 kPa) 2.27 kJ·mol−1
Heat of Vaporization (101.325 kPa) 12.64 kJ·mol−1
Molar Heat Capacity 5R/2 = 20.786 J·mol·K
Most Stable Isotopes
Iso NA Half-Life DM DE (MeV) DP
124Xe 0.095% 124Xe is stable with 70 neutrons
125Xe Syn 16.9 h ε 1.652 125I
126Xe 0.089% 126Xe is stable with 72 neutrons
127Xe Syn 36.345 d ε 0.662 127I
128Xe 1.91% 128Xe is stable with 74 neutrons
129Xe 26.4% 129Xe is stable with 75 neutrons
130Xe 4.07% 130Xe is stable with 76 neutrons
131Xe 21.2% 131Xe is stable with 77 neutrons
132Xe 26.9% 132Xe is stable with 78 neutrons
133Xe Syn 5.247 d β− 0.427 133Cs
134Xe 10.4% 134Xe is stable with 80 neutrons
135Xe Syn 9.14 h β− 1.16 135Cs
136Xe 8.86% 136Xe is stable with 82 neutrons
Xe
6
General Properties
Name Caesium
Symbol Cs
Atomic Number 55
Pronunciation /ˈsiːziəm/ see-zee-əm
Element Category Alkali Metal
Group 1
Period 6
Block s
Atomic Weight 132.9054519(2)
Electron Configuration [Xe] 6s1
Electrons Per Shell 2, 8, 18, 18, 8, 1
Atomic Properties
Oxidation States 1(strongly basic oxide)
Electronegativity 0.79 (Pauling scale)
Ionization Energies 1st: 375.7 kJ·mol−1 2nd: 2234.3 kJ·mol−1 3rd: 3400 kJ·mol−1
Covalent Radius 244±11 pm
Van der Waals Radius 343 pm
Miscellanea
Crystal Structure body-centered cubic
Magnetic Ordering paramagnetic
Thermal Conductivity 35.9 W·m−1·K−1
Speed of Sound
CAS Registry Number 7440-46-2
Vapour Pressure
P (Pa) 1 10 100 1k 10k 100k
at T (K) 418 469 534 623 750 940
Physical Properties
Color
Phase Solid
Density 1.93 g·cm−3
Liquid Density at m.p. 1.843 g·cm−3
Liquid Density at b.p.
Melting Point 301.59 K,28.44 °C,83.19 °F
Boiling Point 944 K,671 °C,1240 °F
Triple Point
Critical Point 1938 K, 9.4 MPa
Heat of Fusion 2.09 kJ·mol−1
Heat of Vaporization 63.9 kJ·mol−1
Molar Heat Capacity 32.210 J·mol−1·K−1
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
133Cs 100% 133Cs is Stable with 78 Neutrons
134Cs Syn
2.0648 y
ε 1.229 134Xe
β− 2.059 134Ba
135Cs Trace 2.3*106 y β− 0.269 135Ba
137Cs Trace 30.17 y β− 1.174 137Ba
Cs
General Properties
Name Barium
Symbol Ba
Atomic Number 56
Pronunciation /ˈbɛəriəm/ bair-ee-əm
Element Category Alkaline Earth Metals
Group 2
Period 6
Block S
Atomic Weight 137.33
Electron Configuration [Xe] 6s2
Electrons Per Shell 2, 8, 18, 18, 8, 2 (Image)
Atomic Properties
Oxidation States 2(Strongly Basic Oxide)
Electronegativity 0.89 (Pauling Scale)
Ionization Energies 1st: 502.9 kJ·mol−1
2nd: 965.2kJ·mol−1
3rd: 3600 kJ·mol−1
Covalent Radius 215±11 pm
Van der Waals Radius 268 pm
Miscellanea
Crystal Structure Body-centered cubic
Magnetic Ordering Paramagnetic
Thermal Conductivity 18.4 W·m−1·K−1
Speed of Sound (20 °C) 1620 m·s−1
CAS Registry Number 7440-39-3
Vapour Pressure
P (Pa) 1 10 100 1k 10k 100k
at T (K) 911 1038 1185 1388 1686 2170
Physical Properties
Color
Phase Solid
Density 3.51 g·cm−3
Liquid Density at m.p. 3.338 g·cm−3
Liquid Density at b.p.
Melting Point 1000 K,727 °C,1341 °F
Boiling Point 2170 K,1897 °C,3447 °F
Triple Point
Critical Point
Heat of Fusion 7.12 kJ·mol−1
Heat of Vaporization 140.3 kJ·mol−1
Molar Heat Capacity 28.07 J·mol−1·K−1
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
130Ba 0.106% 130Ba is stable with 74 neutrons
132Ba 0.101% 132Ba is stable with 76 neutrons
133Ba syn 10.51 y ε 0.517 133Cs
134Ba 2.417% 134Ba is stable with 78 neutrons
135Ba 6.592% 135Ba is stable with 79 neutrons
136Ba 7.854% 136Ba is stable with 80 neutrons
137Ba 11.23% 137Ba is stable with 81 neutrons
138Ba 71.7% 138Ba is stable with 82 neutrons
Ba
General Properties
Name Lanthanum
Symbol La
Atomic Number 57
Pronunciation /ˈlænθənəm/
Element Category Lanthanide
Group n/a
Period 6
Block f
Atomic Weight 138.90547
Electron Configuration [Xe] 5d1 6s2
Electrons Per Shell 2, 8, 18, 18, 9, 2
Atomic Properties
Oxidation States 3, 2 (Strongly Basic Oxide)
Electronegativity 1.10 (Pauling Scale)
Ionization Energies 1st: 538.1 kJ·mol−1
2nd: 1067 kJ·mol−1
3rd: 1850.3kJ·mol−1-1
Atomic radius 187 pm
Covalent Radius 207±8 pm
Van der Waals Radius
Miscellanea
Crystal Structure Hexagonal
Magnetic Ordering Paramagnetic
Thermal Conductivity 13.4 W·m−1·K−1
Speed of Sound (20 °C) 2475 m·s−1
CAS Registry Number 7439-91-0
Mohs hardness 2.5
Vickers hardness 491 MPa
Brinell hardness 363 MPa
Vapour Pressure
P (Pa) 1 10 100 1k 10k 100k
at T (K) 2005 2208 2458 2772 3178 3726
Physical Properties
Phase Solid
Density 6.162 g·cm−3
Liquid Density at m.p. 5.94 g·cm−3
Liquid Density at b.p.
Melting Point 1193 K,920 °C,1688 °F
Boiling Point 3737 K,3464 °C,6267 °F
Heat of Fusion 6.20 kJ·mol−1
Heat of Vaporization 402.1 kJ·mol−1
Molar Heat Capacity 27.11 J·mol−1·K−1
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
137La syn 60,000 yrs ε 0.600 137Ba
138La 0.09% 1.05*1011yrs
ε 1.737 138Ba
β− 1.044 138Ce
139La 99.91% 139La is stable with 82 neutrons
La
General Properties
Name Hafnium
Symbol Hf
Atomic Number 72
Pronunciation /ˈhæfniəm/ haf-nee-əm
Element Category Transition Metal
Group 4
Period 6
Block d
Atomic Weight 178.49
Electron Configuration [Xe] 4f14 5d2 6s2
Electrons Per Shell 2, 8, 18, 32, 10, 2
Atomic Properties
Oxidation States 4, 3, 2 (amphoteric oxide)
Electronegativity 1.3 (Pauling scale)
Ionization Energies 1st: 658.5 kJ·mol−1
2nd: 1440 kJ·mol−1
3rd: 2250 kJ·mol−1
Covalent Radius 175±10 pm
Atomic Radius 159 pm
Miscellanea
Crystal Structure Hexagonal
Magnetic Ordering Paramagnetic
Thermal Conductivity (20 °C) 331 nΩ·m
Thermal expansion (25 °C) 5.9 µm·m−1·K−1
78 GPa (20 °C) 3010 m·s−1
Young's modulus 78 GPa
CAS Registry Number 7440-58-6
Speed of sound (thin rod) (20 °C) 3010 m·s−1
Vickers Hardness 1760 MPa
CAS Registry Number 7440-58-6
Vapour Pressure
P (Pa) 1 10 100 1k 10k 100k
at T (K) 2689 2954 3277 3679 4194 4876
Physical Properties
Phase Solid
Density 13.31 g·cm−3
Liquid Density at m.p. 12 g·cm−3
Liquid Density at b.p.
Melting Point 2506 K,2233 °C,4051 °F
Boiling Point 4876 K,4603 °C,8317 °F
Triple Point
Critical Point
Heat of Fusion 27.2 kJ·mol−1
Heat of Vaporization 571 kJ·mol−1
Molar Heat Capacity 25.73 J·mol−1·K−1
Most Stable Isotopes
iso NA half-life DM DE (MeV) DP
172Hf syn 1.87 y ε 0.350 172Lu
174Hf 0.162% 2*1015 y α 2.495 170Yb
176Hf 5.206% 176Hf is stable with 104 neutrons
177Hf 18.606% 177Hf is stable with 105 neutrons
178Hf 27.297% 178Hf is stable with 106 neutrons
178m2Hf Syn 31y IT 2.446 178Hf
179Hf 13.629% 179Hf is stable with 107 neutrons
180Hf 35.1% 180Hf is stable with 108 neutrons
182Hf Syn 9*106 y β− 0.373 182Ta
Hf
General Properties
Name Tantalum
Symbol Ta
Atomic Number 73
Pronunciation /ˈtæntələm/ tan-təl-əm; previously /tænˈtæliəm/ tan-tal-ee-əm
Element Category Transition Metal
Group 5
Period 6
Block d
Atomic Weight 180.94788
Electron Configuration [Xe] 4f14 5d3 6s2
Electrons Per Shell 2, 8, 18, 32, 11, 2