Question

Which of the following has different bond length and how:-
(a) Cl2O7 (b) O2 (c) H2O2 (d) CrO3
(1) a, d, c
(2) a, c, d
(3) a, b
(4) a, c

Answer 1

As we can see from structural formulas below, only Cl₂O₇ and H₂O₂ have two types of bonds: Cl-O and Cl=O for Cl₂O₇, and H-O and O-O for H₂O₂.
Thus, the right answer is (4) a,c.