Compare Elements

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

Swap
Element comparison
Property Pr Praseodymium Sm Samarium
Atomic Number 59 lower 62 lower
Symbol Pr different Sm different
Name Praseodymium different Samarium different
Atomic Mass 140.9077 lower 150.4 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 1.13 lower 1.17 lower
Atomic Radius 239 higher 229 higher
Ionization Energy 5.464 lower 5.644 lower
Electron Affinity — no data — no data
Oxidation States +3 different +3, +2 different
Melting Point 1204 K (930.85 °C) lower 1347 K (1073.85 °C) lower
Boiling Point 3793 K (3519.85 °C) higher 2067 K (1793.85 °C) higher
Density 6.77 lower 7.52 lower
Electron Configuration [Xe]6s2 4f3 different [Xe]6s2 4f6 different
Year Discovered 1885 different 1879 different

higher lower