Question

Calculate the effective nuclear charge on 4s electron and 3d electron in scandium.​

Answer 1

Answer:

effective 'nuclear charge' for 4s and 3d electrons in Sc is 1.65 and 3 respectively.

Explanation:

Sc [Ar]3d

1

4s

2

Effective nuclear charge Z

eff

=Z−S

where Z = atomic number

and S = screening constant

= 0.35 per electron for electron in nth orbit.

= 0.85 per electron for electrons in (n - 1)th orbit

= 1.00 per electron for electrons in (n - 2)th, (n - 3)th, (n - 4)th orbit

= 0.30 per electron in 1s-orbital (when alone)

This electron 3d

1

is screened by 18 electrons of inner shell electrons.

Thus, σ=

8×1

(n−1)s

2

p

6

+

8×1

(n−2)s

2

p

6

+

2×1

(n−3)s

2

=18

Thus, Z

∗

=21−18=3