Compare the relative stability of given carbocations. CH ₃ - + C -(CH ₃)₂ (I) CH ₃ - + C H-CH ₃ (II) CH ₃ - + C H ₂ (III)

Step-by-step solution

The stability of alkyl carbocations is determined by the +I effect of alkyl groups and hyperconjugation. Carbocation I is a tertiary ( 3^ ) carbocation with 9 -hydrogens, providing maximum hyperconjugation and +I effect. Carbocation II is a secondary ( 2^ ) carbocation with 6 -hydrogens. Carbocation III is a primary ( 1^ ) carbocation with 3 -hydrogens. More the number of -hydrogens, more is the hyperconjugation and greater is the stability. Thus, the relative stability order is I > II > III. Answer: I > II > III