Question

Geometry of ammonia molecule and the hybridisation of nitrogen involved in it are:

• A. $s{p}^3$- hybridisation and tetrahedral geometry
• B. $s{p}^3$- hybridisation and distorted tetrahedral geometry
• C. $s{p}^2$- hybridisation and trianguklar geometry
• D. none of the above

Answer 1

The correct option is B $s{p}^3$- hybridisation and distorted tetrahedral geometry

(i) Hybridisation $=\frac{1}{2}$ [no.of $e^{-}$ in valence shell of central atom + no. of monovalent atoms + charge on anion - charge on cation]
(ii) Shape or geometry of molecule depends on lone pair and bond pair of electrons present in it.
Hybridisation of N in $N{H}_3$
$=\frac{1}{2}(5+3+0)$
$=4$
$\therefore s{p}^3$ hybridisation.
$\because$, its has 3 bond pair and 1 lone pair of electrons, so it has distorted tetrahedron shape.