Question

why do the deviations occur from idealised shape of H2O and nh2 molecule​

Answer 1

Answer:

Since the repulsions on the bond pairs in H2O molecule are greater than that in NH3, the bond angle in water is less than that of ammonia. Although geometry of NH3 and H2O molecules are distorted tetrahedral, bond angle in water is less than that of ammonia.

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