iron vs nickel vs cobalt

iron (chemical element) | nickel (chemical element) | cobalt (chemical element)

Periodic table location

Images

| iron | nickel | cobalt atomic symbol | Fe | Ni | Co atomic number | 26 | 28 | 27 short electronic configuration | [Ar]4s^23d^6 | [Ar]4s^23d^8 | [Ar]4s^23d^7 Aufbau diagram | 3d 4s | 3d 4s | 3d 4s block | d | d | d group | 8 | 10 | 9 period | 4 | 4 | 4 atomic mass | 55.845 u | 58.6934 u | 58.933194 u half-life | (stable) | (stable) | (stable)

| iron | nickel | cobalt phase at STP | solid | solid | solid melting point | 1538 °C | 1455 °C | 1495 °C boiling point | 2861 °C | 2913 °C | 2927 °C molar heat of fusion | 13.8 kJ/mol | 17.2 kJ/mol | 16.2 kJ/mol molar heat of vaporization | 347 kJ/mol | 378 kJ/mol | 375 kJ/mol specific heat at STP | 449 J/(kg K) | 445 J/(kg K) | 421 J/(kg K) (properties at standard conditions)

| iron | nickel | cobalt density | 7.874 g/cm^3 | 8.908 g/cm^3 | 8.9 g/cm^3 liquid density | 6.98 g/cm^3 | 7.81 g/cm^3 | 7.75 g/cm^3 molar volume | 7.092 cm^3/mol | 6.589 cm^3/mol | 6.6 cm^3/mol Mohs hardness | 4 (≈ fluorite) | 4 (≈ fluorite) | 5 (≈ apatite) Vickers hardness | 608 MPa | 638 MPa | 1043 MPa Brinell hardness | 490 MPa | 700 MPa | 700 MPa bulk modulus | 170 GPa | 180 GPa | 180 GPa shear modulus | 82 GPa | 76 GPa | 75 GPa Young's modulus | 211 GPa | 200 GPa | 209 GPa Poisson ratio | 0.29 | 0.31 | 0.31 tensile yield strength | 50 MPa | 59 MPa | 225 MPa ultimate tensile strength | | 317 MPa | sound speed | 4910 m/s | 4970 m/s | 4720 m/s thermal expansion | 1.18×10^-5 K^(-1) | 1.34×10^-5 K^(-1) | 1.3×10^-5 K^(-1) thermal conductivity | 80 W/(m K) | 91 W/(m K) | 100 W/(m K) (properties at standard conditions)

| iron | nickel | cobalt electrical type | conductor | conductor | conductor resistivity | 9.7×10^-8 Ω m (ohm meters) | 7×10^-8 Ω m (ohm meters) | 6×10^-8 Ω m (ohm meters) electrical conductivity | 1×10^7 S/m (siemens per meter) | 1.4×10^7 S/m (siemens per meter) | 1.7×10^7 S/m (siemens per meter) magnetic type | ferromagnetic | ferromagnetic | ferromagnetic Curie point | 1043 K (kelvins) | 631 K (kelvins) | 1394 K (kelvins) work function | (4.67 to 4.81) eV | (5.04 to 5.35) eV | 5 eV (Polycrystalline) threshold frequency | (1.129×10^15 to 1.163×10^15) Hz (hertz) | (1.219×10^15 to 1.294×10^15) Hz (hertz) | 1.209×10^15 Hz (hertz) color | (gray) | (gray) | (gray)

| iron | nickel | cobalt valence | 3 | 2 | 4 electronegativity | 1.83 | 1.91 | 1.88 electron affinity | 15.7 kJ/mol (kilojoules per mole) | 112 kJ/mol (kilojoules per mole) | 63.7 kJ/mol (kilojoules per mole) first ionization energy | 762.5 kJ/mol (kilojoules per mole) | 737.1 kJ/mol (kilojoules per mole) | 760.4 kJ/mol (kilojoules per mole) ionization energies | 762.5 kJ/mol | 1561.9 kJ/mol | 2957 kJ/mol | 5290 kJ/mol | 7240 kJ/mol | 9560 kJ/mol | 12060 kJ/mol | 14580 kJ/mol | 22540 kJ/mol | 25290 kJ/mol | 28000 kJ/mol | 31920 kJ/mol | 34830 kJ/mol | 37840 kJ/mol | 44100 kJ/mol | 47206 kJ/mol | 122200 kJ/mol | 131000 kJ/mol | 140500 kJ/mol | 152600 kJ/mol | 163000 kJ/mol | 737.1 kJ/mol | 1753 kJ/mol | 3395 kJ/mol | 5300 kJ/mol | 7339 kJ/mol | 10400 kJ/mol | 12800 kJ/mol | 15600 kJ/mol | 18600 kJ/mol | 21670 kJ/mol | 30970 kJ/mol | 34000 kJ/mol | 37100 kJ/mol | 41500 kJ/mol | 44800 kJ/mol | 48100 kJ/mol | 55101 kJ/mol | 58570 kJ/mol | 148700 kJ/mol | 159000 kJ/mol | 169400 kJ/mol | 760.4 kJ/mol | 1648 kJ/mol | 3232 kJ/mol | 4950 kJ/mol | 7670 kJ/mol | 9840 kJ/mol | 12440 kJ/mol | 15230 kJ/mol | 17959 kJ/mol | 26570 kJ/mol | 29400 kJ/mol | 32400 kJ/mol | 36600 kJ/mol | 39700 kJ/mol | 42800 kJ/mol | 49396 kJ/mol | 52737 kJ/mol | 134810 kJ/mol | 145170 kJ/mol | 154700 kJ/mol | 167400 kJ/mol

Reactivity

| iron | nickel | cobalt term symbol | ^5D_4 | ^3F_4 | ^4F_(9/2) atomic radius | 140 pm | 135 pm | 135 pm covalent radius | 132 pm | 124 pm | 126 pm van der Waals radius | (unknown) | 163 pm | (unknown) (electronic ground state properties)

| iron | nickel | cobalt universe abundance | 0.11 mass% | 0.006 mass% | 3×10^-4 mass% solar abundance | 0.1 mass% | 0.008 mass% | 4×10^-4 mass% meteorite abundance | 22 mass% | 1.3 mass% | 0.059 mass% crust abundance | 6.3 mass% | 0.0089 mass% | 0.003 mass% ocean abundance | 3×10^-7 mass% | 2×10^-7 mass% | 8×10^-9 mass% human abundance | 0.006 mass% | 1×10^-5 mass% | 2×10^-6 mass% universe molar abundance | 0.002 mol% | 1×10^-4 mol% | 6×10^-6 mol% solar molar abundance | 0.003 mol% | 2×10^-4 mol% | 7×10^-6 mol% meteorite molar abundance | 7.8 mol% | 0.44 mol% | 0.02 mol% ocean molar abundance | 3.3×10^-8 mol% | 2.1×10^-8 mol% | 8×10^-10 mol% crust molar abundance | 2.3 mol% | 0.0032 mol% | 9.9×10^-4 mol% human molar abundance | 6.7×10^-4 mol% | 1.1×10^-6 mol% | 2×10^-7 mol%

| iron | nickel | cobalt half-life | (stable) | (stable) | (stable) stable isotopes | Fe-56 (91.754%) | ... | Ni-58 (68.077%) | ... | Co-59 (100%) unstable isotopes | Fe-60 (2.6 Myr) | ... | Ni-59 (76000 yr) | ... | Co-60 (5.2749 yr) | ...

| iron | nickel | cobalt CAS number | 7439-89-6 | 7440-02-0 | 7440-48-4 PubChem CID number | 23925 | 935 | 104730