Which one of the following molecules contains no bond?
- SO2
- NO2
- CO2
- H2O
Answer
(4) H2O
Solution
SO2: O=S=O — contains π bonds.
NO2: one N=O double bond (resonance) — contains a π bond.
CO2: O=C=O — two π bonds.
H2O: H–O–H — only two O–H σ bonds and two lone pairs on O.
∴ H2O has no π bond.
Answer: (4)