Question

Among the following, the correct statement(s) is/are:
Between $N{H}_3$ and $P{H}_3$

• A. $N{H}_3$ is a better electron donor because the lone pair of electrons occupies the spherical $s$ orbital and is less directional
• B. $P{H}_3$ is a better electron donor because the lone pair of electrons occupies the $s{p}^3$ orbital and is more directional
• C. $N{H}_3$ is a better electron donor because the lone pair of electrons occupies the $s{p}^3$ orbital and is more directional
• D. $P{H}_3$ is a better electron donor because the lone pair of electrons occupies the spherical $s$ orbital and is less directional

Answer 1

The correct option is C $N{H}_3$ is a better electron donor because the lone pair of electrons occupies the $s{p}^3$ orbital and is more directional

In $N{H}_3$ lone pair on $N$ is present in $s{p}^3$ hybridised orbital and hence is more directional.
Whereas in $P{H}_3$ lone pair is present mainly in $3s$ orbital also the bond angle in $P{H}_3$ is almost ${90}^o$ and such compounds are regarded as drago compounds.
So $N{H}_3$ is more basic than $P{H}_3$