**Question: Which of the following carbocations would be expected to rearrange?**- ○ None of these would be expected to rearrange.- ○ Cyclohexyl cation with a methyl group attached (CH₃ on the right side).- ○ Sec-butyl cation with a methyl group attached: CH₃C⁺CH₂CH₃ | CH₃- ○ Cyclohexyl cation with a methyl group attached (CH₃ adjacent to the positive charge).- ○ Cyclohexyl cation with an isolated positive charge at the bottom and a methyl group attached off to the side (CH₃ not adjacent to the positive charge).**Explanation:**- The **first option** is a text stating, "None of these would be expected to rearrange."- The **second option** shows a cyclohexyl ring with a positive charge. A methyl group (CH₃) is attached to the ring at a point not directly connected to the positive charge.- The **third option** displays a branched alkyl chain, specifically a sec-butyl structure. It has a central carbon with a positive charge, bonded to two CH₃ groups and one CH₂CH₃ group.- The **fourth option** is another cyclohexyl ring with a positive charge near a methyl group, possibly indicating a primary cation.- The **fifth option** shows a cyclohexyl ring with a positive charge at one end and a methyl group on an adjacent or equivalent position, isolated from the positive charge.

The given compounds are as follows. The stability of tertiary carbocation is more than secondary carbocation due to more substitution. The order of carbocation for primary, secondary, and tertiary is as follows. 3°>2°>1° The type of arrangement can occur by a hydride shift or alkyl shift. If a secondary carbocation is adjacent to tertiary carbon, bearing hydrogen, a 1,2-hydride shift will take place. If a secondary carbocation is adjacent to quaternary carbon, 1,2- methyl shift will take place. The first compound is a secondary carbocation and rearrangement is not possible. The second compound is a tertiary carbocation and is more stable than secondary carbocation. So, rearrangement is not necessary. The third compound is a tertiary carbocation and is more stable carbocation. The fourth compound is a secondary carbocation and rearrangement is not possible. Answer: The correct option is (a) that is "none of these would be expected to rearrange."