Compare Elements

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

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Element comparison
Property La Lanthanum Os Osmium
Atomic Number 57 lower 76 lower
Symbol La different Os different
Name Lanthanum different Osmium different
Atomic Mass 138.9055 lower 190.2 lower
Category Lanthanides different Transition Metals different
Period 6 same value 6 same value
Group 3 lower 8 lower
Block f-Block different d-Block different
Standard State Solid same value Solid same value
Electronegativity 1.1 lower 2.2 lower
Atomic Radius 240 higher 216 higher
Ionization Energy 5.577 lower 8.7 lower
Electron Affinity 0.5 lower 1.1 lower
Oxidation States +3 different +4, +3 different
Melting Point 1191 K (917.85 °C) lower 3306 K (3032.85 °C) lower
Boiling Point 3737 K (3463.85 °C) lower 5285 K (5011.85 °C) lower
Density 6.15 lower 22.57 lower
Electron Configuration [Xe]6s2 5d1 different [Xe]6s2 4f14 5d6 different
Year Discovered 1839 different 1803 different

higher lower