question_answer

For the following reactions:-      

A. \[~C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}Br\text{ }+\text{ }KOH\to \] \[C{{H}_{3}}CH=C{{H}_{2}}+KBr\text{ }+\text{ }{{H}_{2}}O\]

B.

C.

Which of the following statements is correct?

A) (A) and (b) are elimination reaction and (C) is addition reaction

B) (A) is elimination, (B) is substitution and (C) is addition reaction

C) (A) is elimination, (B) and (C) are substitution reactions

D) (A) is substitution, (B) and (C) are addition reaction

Correct Answer: B

Solution :

\[C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}Br+KOH\to C{{H}_{3}}CH\] \[=C{{H}_{2}}+KBr+\text{ }{{H}_{2}}O\] breaking of \[2\sigma \] bonds and formation of 1 \[1\pi \] bond so it is an example of elimination reaction.    replacement of \[B{{r}^{-}}\] by \[\text{O}{{\text{H}}^{\text{--}}}\] is substitution reaction   breaking of \[1\pi \] bond and formation of \[2\sigma \] bonds is addition reaction