Compare Elements

Compare two chemical elements side by side across 19 atomic and physical properties.

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Element comparison
Property Mg Magnesium Ra Radium
Atomic Number 12 lower 88 lower
Symbol Mg different Ra different
Name Magnesium different Radium different
Atomic Mass 24.305 lower 226.0254 lower
Category Alkaline Earth Metals same value Alkaline Earth Metals same value
Period 3 lower 7 lower
Group 2 same value 2 same value
Block s-Block same value s-Block same value
Standard State Solid same value Solid same value
Electronegativity 1.31 higher 0.9 higher
Atomic Radius 173 lower 283 lower
Ionization Energy 7.646 higher 5.279 higher
Electron Affinity — no data — no data
Oxidation States +2 same value +2 same value
Melting Point 923 K (649.85 °C) lower 973 K (699.85 °C) lower
Boiling Point 1363 K (1089.85 °C) lower 1413 K (1139.85 °C) lower
Density 1.74 lower 5 lower
Electron Configuration [Ne]3s2 different [Rn]7s2 different
Year Discovered 1808 different 1898 different

higher lower