The correct order of bond angles in the following compounds/species is :
- CO2 < NH3 < H2O < +NH4
- H2O < NH3 < +NH4 < CO2
- H2O < +NH4 < NH3 < CO2
- H2O < +NH4 = NH3 < CO2
Answer
(2) H2O < NH3 < +NH4 < CO2
Solution
H2O: sp3, two lone pairs (bent) 104.5°
NH3: sp3, one lone pair (pyramidal) 107°
NH4+: sp3, no lone pair (tetrahedral) 109.5°
CO2: sp, linear 180°
As per NCERT (VSEPR theory), lone pair–bond pair repulsion is greater than bond pair–bond pair repulsion, so more lone pairs give a smaller bond angle.
H2O < NH3 < NH4+ < CO2
Answer: (2)