Compare Elements

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

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Element comparison
Property Ca Calcium Ra Radium
Atomic Number 20 lower 88 lower
Symbol Ca different Ra different
Name Calcium different Radium different
Atomic Mass 40.08 lower 226.0254 lower
Category Alkaline Earth Metals same value Alkaline Earth Metals same value
Period 4 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 higher 0.9 higher
Atomic Radius 231 lower 283 lower
Ionization Energy 6.113 higher 5.279 higher
Electron Affinity — no data — no data
Oxidation States +2 same value +2 same value
Melting Point 1115 K (841.85 °C) higher 973 K (699.85 °C) higher
Boiling Point 1757 K (1483.85 °C) higher 1413 K (1139.85 °C) higher
Density 1.54 lower 5 lower
Electron Configuration [Ar]4s2 different [Rn]7s2 different
Year Discovered Ancient different 1898 different

higher lower