Compare Elements

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

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Element comparison
Property La Lanthanum Pr Praseodymium
Atomic Number 57 lower 59 lower
Symbol La different Pr different
Name Lanthanum different Praseodymium different
Atomic Mass 138.9055 lower 140.9077 lower
Category Lanthanides same value Lanthanides same value
Period 6 same value 6 same value
Group 3 same value 3 same value
Block f-Block same value f-Block same value
Standard State Solid same value Solid same value
Electronegativity 1.1 lower 1.13 lower
Atomic Radius 240 higher 239 higher
Ionization Energy 5.577 higher 5.464 higher
Electron Affinity 0.5 no data — no data
Oxidation States +3 same value +3 same value
Melting Point 1191 K (917.85 °C) lower 1204 K (930.85 °C) lower
Boiling Point 3737 K (3463.85 °C) lower 3793 K (3519.85 °C) lower
Density 6.15 lower 6.77 lower
Electron Configuration [Xe]6s2 5d1 different [Xe]6s2 4f3 different
Year Discovered 1839 different 1885 different

higher lower