Effective nuclear charge `(Z_(eff))` is the net attractive force on electrons under consideration and is equal to:
`Z_(eff) = Z - sigma` (nuclear charge - screening constant). `Z_(eff)` or `sigma` is calculated by Slater's formula, as given.
If one electrons is present in the outermst orbit, there will be no screening in that orbital. Each electrons contribute, `0.35` (total electrons minus one electron) present in the outermost shell.
A contribution of `0.85` for each electrons is taken in the `(n - 1)th` shell.
Which of the following statement is wrong?

Options

A. `IE_(1)` of `Ga gt Al`, due ot imperfect shielding of `3d`-orbitals in `Ga`.
B. `IE_(1)` of `Ga lt Al`, due ot perfect shielding of `3d`-orbitals in `Ga`.
C. The atomic size of `Ga` and `Al` are almost same because of poor shielding effect of electrons in `d`-orbitals as the effective nuclear charge increases in `Ga`.
D. `IE_(1)` of group `16` elements is less than that of group `15` elements.

Answer

B

Explanation

Statement (b) is wrong.