Question

Why 1st ionization energy of radium is higher than barium?​

Answer 1

Answer:

it is because if lanthanoide contraction .... there is a poor shielding effect in radium so its electons are bound to the nucleus very strongly then in barium and therfor its ionisation energy is higher than barium.....

Answer 2

Answer:

is because if lanthanoide contraction .... there is a poor shielding effect in radium so its electons are bound to the nucleus very strongly then in barium and therfor its ionisation energy is higher than barium.....

A radium nucleus has 32 more protons than a barium nucleus (57% more), so its attractive force on any of its electrons is correspondingly greater. This increases the amount of energy needed for ionisation. ... This increases the amount of energy needed for ionization.