Input interpretation
rubidium (chemical element) | radium (chemical element) | magnesium (chemical element)
Periodic table location
Periodic table location
Images
Images
Basic elemental properties
| rubidium | radium | magnesium atomic symbol | Rb | Ra | Mg atomic number | 37 | 88 | 12 short electronic configuration | [Kr]5s^1 | [Rn]7s^2 | [Ne]3s^2 Aufbau diagram | 5s | 7s | 3s block | s | s | s group | 1 | 2 | 2 period | 5 | 7 | 3 atomic mass | 85.4678 u | 226 u | 24.305 u half-life | (stable) | 1600 yr | (stable)
Thermodynamic properties
| rubidium | radium | magnesium phase at STP | solid | solid | solid melting point | 39.31 °C | 700 °C | 650 °C boiling point | 688 °C | 1737 °C | 1090 °C critical temperature | 2093 K | | (unknown) critical pressure | 16 MPa | | (unknown) molar heat of fusion | 2.19 kJ/mol | 8 kJ/mol | 8.7 kJ/mol molar heat of vaporization | 72 kJ/mol | 125 kJ/mol | 128 kJ/mol specific heat at STP | 364 J/(kg K) | 92 J/(kg K) | 1020 J/(kg K) (properties at standard conditions)
Material properties
| rubidium | radium | magnesium density | 1.532 g/cm^3 | 5 g/cm^3 | 1.738 g/cm^3 liquid density | 1.46 g/cm^3 | | 1.584 g/cm^3 molar volume | 55.79 cm^3/mol | 45 cm^3/mol | 13.98 cm^3/mol Mohs hardness | 0.3 (between talc and gypsum) | | 2.5 (between gypsum and calcite) Brinell hardness | 0.216 MPa | | 260 MPa bulk modulus | 2.5 GPa | | 45 GPa shear modulus | | | 17 GPa Young's modulus | 2.4 GPa | | 45 GPa Poisson ratio | | | 0.29 sound speed | 1300 m/s | | 4602 m/s thermal expansion | | | 2.5×10^-5 K^(-1) thermal conductivity | 58 W/(m K) | 19 W/(m K) | 160 W/(m K) (properties at standard conditions)
Electromagnetic properties
| rubidium | radium | magnesium electrical type | conductor | conductor | conductor resistivity | 1.2×10^-7 Ω m (ohm meters) | 1×10^-6 Ω m (ohm meters) | 4.4×10^-8 Ω m (ohm meters) electrical conductivity | 8.3×10^6 S/m (siemens per meter) | 1×10^6 S/m (siemens per meter) | 2.3×10^7 S/m (siemens per meter) magnetic type | paramagnetic | | paramagnetic volume magnetic susceptibility | 3.98×10^-6 | | 1.2×10^-5 mass magnetic susceptibility | 2.6×10^-9 m^3/kg (cubic meters per kilogram) | | 6.9×10^-9 m^3/kg (cubic meters per kilogram) molar magnetic susceptibility | 2.22×10^-10 m^3/mol (cubic meters per mole) | | 1.68×10^-10 m^3/mol (cubic meters per mole) work function | 2.26 eV (Polycrystalline) | | 3.66 eV (Polycrystalline) threshold frequency | 5.467×10^14 Hz (hertz) | | 8.85×10^14 Hz (hertz) color | (silver) | (silver) | (silver)
Reactivity
| rubidium | radium | magnesium valence | 1 | 2 | 2 electronegativity | 0.82 | 0.9 | 1.31 electron affinity | 46.9 kJ/mol (kilojoules per mole) | | 0 kJ/mol (kilojoules per mole) first ionization energy | 403 kJ/mol (kilojoules per mole) | 509.3 kJ/mol (kilojoules per mole) | 737.7 kJ/mol (kilojoules per mole) ionization energies | 403 kJ/mol | 2633 kJ/mol | 3860 kJ/mol | 5080 kJ/mol | 6850 kJ/mol | 8140 kJ/mol | 9570 kJ/mol | 13120 kJ/mol | 14500 kJ/mol | 26740 kJ/mol | 509.3 kJ/mol | 979 kJ/mol | 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
Reactivity
Atomic properties
| rubidium | radium | magnesium term symbol | ^2S_(1/2) | ^1S_0 | ^1S_0 atomic radius | 235 pm | 215 pm | 150 pm covalent radius | 220 pm | 221 pm | 141 pm van der Waals radius | | | 173 pm (electronic ground state properties)
Abundances
| rubidium | radium | magnesium universe abundance | 1×10^-6 mass% | | 0.06 mass% solar abundance | 3×10^-6 mass% | | 0.07 mass% meteorite abundance | 3.2×10^-4 mass% | | 12 mass% crust abundance | 0.006 mass% | 9.9×10^-12 mass% | 2.9 mass% ocean abundance | 1.2×10^-5 mass% | 1×10^-15 mass% | 0.13 mass% human abundance | 4.6×10^-4 mass% | 1×10^-13 mass% | 0.027 mass% universe molar abundance | 1×10^-8 mol% | | 0.003 mol% solar molar abundance | 4×10^-8 mol% | | 0.003 mol% meteorite molar abundance | 7.8×10^-5 mol% | | 10 mol% ocean molar abundance | 8.7×10^-7 mol% | 3×10^-6 mol% | 0.034 mol% crust molar abundance | 0.0014 mol% | 9.9×10^-13 mol% | 2.5 mol% human molar abundance | 3.4×10^-5 mol% | 3×10^-6 mol% | 0.007 mol%