Compare Elements

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

Swap
Element comparison
Property Pr Praseodymium Ac Actinium
Atomic Number 59 lower 89 lower
Symbol Pr different Ac different
Name Praseodymium different Actinium different
Atomic Mass 140.9077 lower 227.0277 lower
Category Lanthanides different Actinides different
Period 6 lower 7 lower
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 higher 1.1 higher
Atomic Radius 239 lower 260 lower
Ionization Energy 5.464 higher 5.17 higher
Electron Affinity — no data — no data
Oxidation States +3 same value +3 same value
Melting Point 1204 K (930.85 °C) lower 1324 K (1050.85 °C) lower
Boiling Point 3793 K (3519.85 °C) higher 3471 K (3197.85 °C) higher
Density 6.77 lower 10.07 lower
Electron Configuration [Xe]6s2 4f3 different [Rn]7s2 6d1 different
Year Discovered 1885 different 1899 different

higher lower