Question

Why first ionization energies of 5d elements are higher than those of 3d and 4d elements?

Answer 1

Answer:

1st ionisation energies of 5d elements are higher than those of 3d or 4d elements this is due to the greater effective nuclear charge acting on outer valence electrons because of weak shielding by 4f electrons.

Answer 2

Answer:

5d is half filled subshell

Explanation:

d subshell have 5orbital , in which we can fill total 10 ē

if in d subshell 5ē present so it is half filled . half filled is more stable than vacant or 3 or 4 becoz atoms want to be stable...!