magnesium vs hydrogen vs potassium

magnesium (chemical element) | hydrogen (chemical element) | potassium (chemical element)

Periodic table location

Images

| magnesium | hydrogen | potassium atomic symbol | Mg | H | K atomic number | 12 | 1 | 19 short electronic configuration | [Ne]3s^2 | 1s^1 | [Ar]4s^1 Aufbau diagram | 3s | 1s | 4s block | s | s | s group | 2 | 1 | 1 period | 3 | 1 | 4 atomic mass | 24.305 u | 1.008 u | 39.0983 u half-life | (stable) | (stable) | (stable)

| magnesium | hydrogen | potassium phase at STP | solid | gas | solid melting point | 650 °C | -259.14 °C | 63.38 °C boiling point | 1090 °C | -252.87 °C | 759 °C critical temperature | (unknown) | 32.97 K | 2223 K critical pressure | (unknown) | 1.293 MPa | 16 MPa molar heat of fusion | 8.7 kJ/mol | 0.558 kJ/mol | 2.33 kJ/mol molar heat of vaporization | 128 kJ/mol | 0.452 kJ/mol | 76.9 kJ/mol specific heat at STP | 1020 J/(kg K) | 14300 J/(kg K) | 757 J/(kg K) adiabatic index | | 7/5 | (properties at standard conditions)

| magnesium | hydrogen | potassium density | 1.738 g/cm^3 | 8.99×10^-5 g/cm^3 | 0.856 g/cm^3 liquid density | 1.584 g/cm^3 | | 0.828 g/cm^3 molar volume | 13.98 cm^3/mol | 11200 cm^3/mol | 45.7 cm^3/mol Mohs hardness | 2.5 (between gypsum and calcite) | | 0.4 (between talc and gypsum) Brinell hardness | 260 MPa | | 0.363 MPa bulk modulus | 45 GPa | | 3.1 GPa shear modulus | 17 GPa | | 1.3 GPa Young's modulus | 45 GPa | | Poisson ratio | 0.29 | | refractive index | (unknown) | 1.000132 | sound speed | 4602 m/s | 1270 m/s | 2000 m/s thermal expansion | 2.5×10^-5 K^(-1) | | thermal conductivity | 160 W/(m K) | 0.1805 W/(m K) | 100 W/(m K) (properties at standard conditions)

| magnesium | hydrogen | potassium electrical type | conductor | | conductor resistivity | 4.4×10^-8 Ω m (ohm meters) | | 7×10^-8 Ω m (ohm meters) electrical conductivity | 2.3×10^7 S/m (siemens per meter) | | 1.4×10^7 S/m (siemens per meter) magnetic type | paramagnetic | diamagnetic | paramagnetic volume magnetic susceptibility | 1.2×10^-5 | -2.23×10^-9 | 5.74×10^-6 mass magnetic susceptibility | 6.9×10^-9 m^3/kg (cubic meters per kilogram) | -2.48×10^-8 m^3/kg (cubic meters per kilogram) | 6.7×10^-9 m^3/kg (cubic meters per kilogram) molar magnetic susceptibility | 1.68×10^-10 m^3/mol (cubic meters per mole) | -4.999×10^-11 m^3/mol (cubic meters per mole) | 2.62×10^-10 m^3/mol (cubic meters per mole) work function | 3.66 eV (Polycrystalline) | | 2.29 eV (Polycrystalline) threshold frequency | 8.85×10^14 Hz (hertz) | | 5.537×10^14 Hz (hertz) color | (silver) | (colorless) | (silver) refractive index | (unknown) | 1.000132 |

| magnesium | hydrogen | potassium valence | 2 | 1 | 1 electronegativity | 1.31 | 2.2 | 0.82 electron affinity | 0 kJ/mol (kilojoules per mole) | 72.8 kJ/mol (kilojoules per mole) | 48.4 kJ/mol (kilojoules per mole) first ionization energy | 737.7 kJ/mol (kilojoules per mole) | 1312 kJ/mol (kilojoules per mole) | 418.8 kJ/mol (kilojoules per mole) ionization energies | 737.7 kJ/mol | 1450.7 kJ/mol | 7732.7 kJ/mol | 10542.5 kJ/mol | 13630 kJ/mol | 18020 kJ/mol | 21711 kJ/mol | 25661 kJ/mol | 31653 kJ/mol | 35458 kJ/mol | 1312 kJ/mol | 418.8 kJ/mol | 3052 kJ/mol | 4420 kJ/mol | 5877 kJ/mol | 7975 kJ/mol | 9590 kJ/mol | 11343 kJ/mol | 14944 kJ/mol | 16963.7 kJ/mol | 48610 kJ/mol

Reactivity

| magnesium | hydrogen | potassium term symbol | ^1S_0 | ^2S_(1/2) | ^2S_(1/2) atomic radius | 150 pm | 25 pm | 220 pm covalent radius | 141 pm | 31 pm | 203 pm van der Waals radius | 173 pm | 120 pm | 275 pm (electronic ground state properties)

| magnesium | hydrogen | potassium universe abundance | 0.06 mass% | 75 mass% | 3×10^-4 mass% solar abundance | 0.07 mass% | 75 mass% | 4×10^-4 mass% meteorite abundance | 12 mass% | 2.4 mass% | 0.07 mass% crust abundance | 2.9 mass% | 0.15 mass% | 1.5 mass% ocean abundance | 0.13 mass% | 11 mass% | 0.042 mass% human abundance | 0.027 mass% | 10 mass% | 0.2 mass% universe molar abundance | 0.003 mol% | 93 mol% | 1×10^-5 mol% solar molar abundance | 0.003 mol% | 93 mol% | 9.9×10^-6 mol% meteorite molar abundance | 10 mol% | 17 mol% | 0.037 mol% ocean molar abundance | 0.034 mol% | 66 mol% | 0.0066 mol% crust molar abundance | 2.5 mol% | 3.1 mol% | 0.78 mol% human molar abundance | 0.007 mol% | 62 mol% | 0.032 mol%

| magnesium | hydrogen | potassium half-life | (stable) | (stable) | (stable) stable isotopes | Mg-24 (78.99%) | Mg-26 (11.01%) | Mg-25 (10%) | H-1 (99.985%) | H-2 (1.5×10^-4) | K-39 (93.2581%) | K-41 (6.7302%) nuclear spin | Mg-19: 1/2^- | Mg-20: 0^+ | Mg-21: 5/2^+ | Mg-22: 0^+ | Mg-23: 3/2^+ | Mg-24: 0^+ | Mg-25: 5/2^+ | Mg-26: 0^+ | Mg-27: 1/2^+ | Mg-28: 0^+ | Mg-29: 3/2^+ | Mg-30: 0^+ | Mg-31: 1/2^+ | Mg-32: 0^+ | Mg-33: 3/2^+ | Mg-34: 0^+ | Mg-35: 7/2^- | Mg-36: 0^+ | Mg-37: 7/2^- | Mg-38: 0^+ | Mg-39: 7/2^- | Mg-40: 0^+ | H-1: 1/2^+ | H-2: 1^+ | H-3: 1/2^+ | H-4: 2^- | H-5: 1/2^+ | H-6: 2^- | H-7: 1/2^+ | K-32: 1^+ | K-33: 3/2^+ | K-34: 1^+ | K-35: 3/2^+ | K-36: 2^+ | K-37: 3/2^+ | K-38: 3^+ | K-39: 3/2^+ | K-40: 4^- | K-41: 3/2^+ | K-42: 2^- | K-43: 3/2^+ | K-44: 2^- | K-45: 3/2^+ | K-46: 2^- | K-47: 1/2^+ | K-48: 2^- | K-49: 3/2^+ | K-52: 2^- | K-53: 3/2^+ | K-54: 2^- | K-55: 3/2^+ unstable isotopes | Mg-28 (20.915 h) | Mg-27 (9.458 min) | Mg-23 (11.317 s) | Mg-22 (3.8755 s) | Mg-29 (1.3 s) | Mg-30 (335 ms) | Mg-31 (232 ms) | Mg-21 (122 ms) | Mg-33 (90.5 ms) | Mg-20 (90 ms) | Mg-32 (86 ms) | Mg-35 (70 ms) | Mg-34 (20 ms) | Mg-36 (3.9 ms) | Mg-38 (260 ns) | Mg-37 (260 ns) | Mg-39 (180 ns) | Mg-40 (170 ns) | H-3 (12.32 yr) | H-6 (0.29 zs) | H-4 (0.139 zs) | H-5 (0.08 zs) | H-7 (0.023 zs) | K-40 (1.248 Gyr) | K-43 (22.3 h) | K-42 (12.321 h) | K-44 (22.13 min) | K-45 (17.81 min) | K-38 (7.637 min) | K-46 (105 s) | K-47 (17.5 s) | K-48 (6.8 s) | K-49 (1.26 s) | K-37 (1.226 s) | K-50 (472 ms) | K-51 (365 ms) | K-36 (342 ms) | K-35 (178 ms) | K-52 (105 ms) | K-53 (30 ms) | K-54 (10 ms) | K-55 (3 ms) | K-34 (25 ns) | K-33 (25 ns) neutron cross-section | 0.063 b | 0.332 b | 2.1 b neutron mass absorption | 1×10^-4 m^2/kg | 0.011 m^2/kg | 0.0018 m^2/kg

| magnesium | hydrogen | potassium CAS number | 7439-95-4 | 1333-74-0 | 7440-09-7 PubChem CID number | 5462224 | 783 | 5462222