Question

The $C-C$ and $Si-C$ inter-atomic distance are $154pm$ and $188pm$. the atomic radius of $Si$ is:

• A. $77pm$
• B. $94pm$
• C. $114pm$
• D. $111pm$

Answer 1

The correct option is D $111pm$

Radius of $C=\frac{154}{2}=77$ $pm=r_C$

$C-C$ is covalent bond.

For $Si-C$ bond.

$r_{Si}+r_C=188$

$⟹77+r_{Si}=188$

$⟹r_{Si}=188-77$

$⟹r_{Si}=111$ $pm$