English
Karnataka Board PUCPUC Science 2nd PUC Class 12

Bond angle in PH4+ is higher than that in PH3. Why? - Chemistry

Advertisements
Advertisements

Question

Bond angle in `PH_(4)^(+)` is higher than that in PH3. Why?

Solution 1

In PH3, P is sp3 hybridized. Three orbitals are involved in bonding with three hydrogen atoms and the fourth one contains a lone pair. As lone pair-bond pair repulsion is stronger than bond pair-bond pair repulsion, the tetrahedral shape associated with sp3 bonding is changed to pyramidal. PH3 combines with a proton to form `PH_4^(+)` in which the lone pair is absent. Due to the absence of lone pair in `PH_4^(+)`, there is no lone pair-bond pair repulsion. Hence, the bond angle in is higher than the bond angle in PH3

shaalaa.com

Solution 2

P in PH3 is sp3-hybridized with 3 bond pairs and one lone pair around P. Due to stronger lp-bp repulsions than bp-bp repulsions, tetrahedral angle decreases from 109°28′ to 93.6°. As a result, PH3 is pyramidal. In PH4+, there are 4 bp’s and no lone pair. As a result, there are only identical bp-bp repulsions so that PH4+ assumes tetrahedral geometry and the bond angle is 109°28′.Hence, bond angle of PH4+ > bond angle of PH3

shaalaa.com
  Is there an error in this question or solution?
Chapter 7: The p-block Elements - Intext Questions [Page 177]

APPEARS IN

NCERT Chemistry [English] Class 12
Chapter 7 The p-block Elements
Intext Questions | Q 7 | Page 177
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×