JEE Main levelSingle correct optionDifficulty 2 of 3g1226
The ion shown is a hybrid of two resonance contributors, one of which is drawn. Which statement about the contributors is correct?
AThe drawn form is the major contributor because every atom has a complete octet
BThe form with a C=O double bond and a sextet carbon is major because it has a neutral oxygen
CBoth contributors are equal because they are related by resonance
DNeither contributes, because the ion is a localised cation
Answer: A
The ion shown is the acetylium (acylium) ion. The other contributor has a C=O double bond and a sextet carbon. The drawn contributor has a C-O triple bond with complete octets on both atoms, so it is the major contributor.