Question

The correct decreasing order of bond angles of NO2-,NO2+ and NO2 is-
A) NO2->NO2+>NO2
B) NO2->NO2>NO2+
C)NO2>NO2->NO2+
D)NO2+>NO2>NO2-

Answer 1

The option D) NO2+ > NO2 > NO2- is correct.

• NO2+ has no lone pair, only bond pairs so the molecule is linear leading to a bond angle of 180o.
• NO2 has one lone electron and it exerts a less repulsion than a lone pair of electrons, so the spread out of two bonding oxygen atoms is more leading to a bond angle greater than 120o.
• NO2- has 1 lone pair on nitrogen. As the lone pair electron repulsion is more than the bonding electrons so the bond angle will be less than 120o.
• 180 > greater than 120 > less than 120
• NO2+ > NO2 > NO2-