Question

Explain the non linear shape of H2S and non polar shape of PCl3 using VSEPR theory

Answer 1

we know according to VSEPR theory
the geometry of the molecule depends upon the total number of valence electron pairs (either bond pair or lone pair )around the central atom and the repulsions between these electron pairs.
here
H2S:-
first we find hybridization
valence shell electrons of the central metal=6
no of monovalent atom=2
total positive charge on molecule =0
total negative charge on molecule=0

hybridization=1/2 (6+2-0+0)=4
hence hybridization of H2S is sp3

H/:S:\H in this type of structure found because hybridization sp3 and two lone pairs,
and two bond pairs exist.
we also know sp3 hybridization has tetrahydral shape but here two lone pair , so
shape is angular .

PCl3:-
hybridization=1/2 (5+3-0+0)=4

hence hybridization is sp3 .and one lone pair,
so, pyrimidal shape form by PCl3.hence no cut their charge by each others. hence PCl3 should polar
Cl-----(:)P-----Cl
|Cl
but P and Cl share charge equally due to all monovalent atom (Cl) are same and polarity became zero.
so, PCl3 has non polar