Arrange the following carbocations in decreasing order of their stability: (i) (ii) (iii) (iv)

Step-by-step solution

The stability of carbocations is determined by the +I effect, hyperconjugation (number of -hydrogens), and the hybridization of the carbon bearing the positive charge. Carbocation (i) is a vinylic carbocation where the positive charge is present on an sp -hybridized carbon. Due to the high s -character ( 50 % ) and higher electronegativity of the sp carbon, it is highly unstable and the least stable among the given options. Carbocation (ii) is a primary ( 1^ ) carbocation (cyclohexylmethyl cation). It is stabilized