Arrange the following groups in the increasing order of their effect: — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

Heavier isotopes of hydrogen form slightly shorter, stronger, and less vibrating bonds with carbon, bringing their electron density closer to the carbon nucleus. This increases their $+I$ effect relative to lighter isotopes. Alkyl groups like $-CH_3$ possess a stronger $+I$ effect than any hydrogen isotope.