Question

The correct order in which the $O-O$ bond length increases in the following is:

• A. $H_2{O}_2<O_2<O_3$
• B. $O_3<H_2{O}_2<O_2$
• C. $O_2<H_2{O}_2<O_3$
• D. $O_2<O_3<H_2{O}_2$

Answer 1

The correct option is D $O_2<O_3<H_2{O}_2$


Greater the bond order, smaller the bond length. In $H_2{O}_2$, there is a single bond between the two $O$ atoms which has the greatest bond length. In $O_3$ due to resonance, the bond order becomes 1.5 (between double and single bond) and in $O_2$ there is a perfect double bond which has the smallest bond length.