Question

Which molecule is not linear?

• A. $C{O}_2$
• B. $S{O}_3$
• C. $C_2{H}_2$
• D. $MgC{l}_2$

Answer 1

Answer: (B)

Hybridisation and shape of molecule is decided by following formula.
$H=\frac{1}{2}(V+X-C+A)$
where H = hybridisation
$V=$ number of electrons in valance shall of central atom
$X=$ number of monovalent atoms
$C=$ charge on cation
$A=$ charge on anion
$C{O}_2$
$H=\frac{1}{2}(4+0-0+0)=2$
$\therefore sp$ hybridisation so shape is linear.
$S{O}_{2}H=\frac{1}{2}(6+0-0+0)=3$
$\therefore s{p}^2$ hybridisation so shape is trigonal planar.
$C_2{H}_2$ Each carbon is sp hybridised and linear in shape.
$MgC{l}_{2}H=\frac{1}{2}(2+2-0+0)$
$\therefore sp$ hybridisation and linear is the shape.