How Bond angle in PH4+ is higher than in PH3 ?

In case of both molecules the hybridization of P is sp³ but there is a difference.

In case of PH3 we have a lone pair present on the phosphorus atom. This lone pair pushes the bond pairs downwards due to lone pair-bond pair repulsions which decreases the bond angle in P-H-P atoms, as shown below.

Bond angle in PH3

But in case of PH4+ the lone pair of phosphorus is donated to the H+ (hydronium ion) for making a coordinate bond. Thus there is not any lone pair on phosphorus atom.

As the bond pair-bond pair repulsions are quite lesser than lone pair-bond pair so it gets proper tetrahedral structure.

The structure with least repulsions will have higher bond angle. The structure is as shown below.

Published by ankushmaster

I am M.Sc (chemistry ) from punjabi university. I am a science teacher with expertise in chemistry, with 8 years of experiance in teaching. i am getting a handsome salary , now i wish to help out the people who need me UNCONDITIONALLY. and I am constantly working on creating a new and easy way of learning the tough things in an effective way. I am constantly working to make authentic and reliable information to be shared with my students and widen the horizons of knowledge.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: