In: Chemistry
The bond angle in NH3 is significantly smaller than the ideal bond angle of 109.5° because of the lone pair on the central atom. Which best explains why the bond angle in SO2 is very close to 120° despite there being a lone pair on the central atom?
In SO2 you have 2 double bonds and one lone pair. 3 electron regions so the default angle is 120 degrees. The extra repulsion between the loanpair and double bond accounts for reduction to 119.
In NH3 you have 3 single bond and one loan pair. 4 electron regions so the default angle is about 109 Degrees.
Mainly In NH3 3 atoms and one loan pair leads to 107.3 Deg
In SO2 2 atoms and one loan pair leads to ~ 119 Deg