Question

E.N. of Si is ______. (Covalent radius of Si = 1.175 Å)

Options

• 0.096

• 1.823

• 0.025

• 5.369

Answer 1

E.N. of Si is 1.823.

Explanation:

(E.N.) Allred Rochow

${\displaystyle =0.744+\frac{0.359}{{\text{r}}^2}{\text{Z}}_{\text{eff}}}$

${\displaystyle {\text{Z}}_{\text{eff}}\text{of}{\text{Si}}^{+}\Rightarrow \text{Si}=1{\text{s}}^2 2{\text{s}}^2 2{\text{p}}^6 3{\text{s}}^2 3{\text{p}}^2}$

${\displaystyle \therefore {\text{Z}}_{\text{eff}}=14-(3\times 0.35+8\times 0.85+2\times 1)}$

= 4.15

∴ E.N. = ${\displaystyle 0.744+\frac{0.359}{\left(1.175\right)}\times 4.15}$

∴ E.N. = 1.823