Compare Elements

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

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Element comparison
Property Fr Francium Cs Cesium
Atomic Number 87 higher 55 higher
Symbol Fr different Cs different
Name Francium different Cesium different
Atomic Mass 223.0197 higher 132.9055 higher
Category Alkali Metals same value Alkali Metals same value
Period 7 higher 6 higher
Group 1 same value 1 same value
Block s-Block same value s-Block same value
Standard State Solid same value Solid same value
Electronegativity 0.7 lower 0.79 lower
Atomic Radius 348 higher 343 higher
Ionization Energy 3.9 higher 3.894 higher
Electron Affinity 0.47 lower 0.472 lower
Oxidation States +1 same value +1 same value
Melting Point 300 K (26.85 °C) lower 301.59 K (28.44 °C) lower
Boiling Point — no data 944 K (670.85 °C) no data
Density — no data 1.93 no data
Electron Configuration [Rn]7s1 different [Xe]6s1 different
Year Discovered 1939 different 1860 different

higher lower