MCQs on Molecular Orbital Theory

NOTE- Answers are highlighted in Bold and Colour

1. Which among the following has the shortest C-C bond length?

(a) Ethene

(b) Ethane

(c) Benzene

(d) Ethyne

2. The oxygen molecule is paramagnetic. It can be explained by

(a) Resonance

(b) Hybridisation

(c) Valence bond theory

(d) Molecular orbital theory

3. Find the paramagnetic species

(a) CN–

(b) NO+

(c) CO

(d) O2–

4. Find the diamagnetic species

(a) H2

(b) H2–

(c) He2+

(d) H2+

5. Which of the following pairs has the same bond order?

(a) O2+, NO+

(b) N2, O2

(c) O22-, B2

(d) NO, CO

6. Each P of P4O10 is attached to how many oxygen atoms?

(a) 3

(b) 2.5

(c) 2

(d) 4

7. When O2 changes to O2–, the electron goes to which of the orbitals?

(a) 𝜋 orbital

(b) 𝜎 orbital

(c) 𝜋* orbital

(d) 𝜎* orbital

8. O-O bond length is minimum in

(a) O2–

(b) O2

(c) O2+

(d) O22-

9. Which of the following is not paramagnetic?

(a) CO

(b) N2+

(c) NO

(d) O2–

10. Find the molecule having the highest bond order

(a) O2+

(b) O2–

(c) O22-

(d) O2