question_answer 33)

    Which of the following are correct structural isomers of butane? (i)        (ii)              (iii)         (iv) (a) (i) and (iii)                     (b) (ii) and (iv)                   (c) (i) and (ii)                      (d) (iii) and (iv)  

Answer:

                  (a) Structure (i) is n-butane Structure (iii) is iso-butane Since, molecular formula is same, only structures are different. So, (i) and (iii) are isomers while structure (ii) and (iv) have molecular formula .