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JEE Main levelSingle correct optionDifficulty 2 of 3g3022

The methoxymethyl cation $CH X_{3} - O - CH X_{2} X^{+}$ is more stable than the ethyl cation $CH X_{3} CH X_{2} X^{+}$ because:

Aoxygen is more electronegative and withdraws electrons by $- I$ , which stabilises a cation
Bthe oxygen lone pair donates into the empty $p$ orbital ( $+ M$ , oxocarbenium resonance)
C $CH X_{3} - O - CH X_{2} X^{+}$ is a tertiary cation
Dthe ethyl cation cannot show hyperconjugation

Answer: B

In

CH X_{3} - O X^{+} = CH X_{2}

every atom has an octet, so this resonance form is the major contributor. The -I effect of oxygen alone would destabilise a cation, so option 2 is wrong.

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