Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the most appropriate answer from the options given below :
- (A) is correct but (R) is not correct
- Both (A) and (R) are correct and (R) is the correct explanation of (A)
- (A) is not correct but (R) is correct
- Both (A) and (R) are correct but (R) is not the correct explanation of (A)
Answer
(1) (A) is correct but (R) is not correct
Solution
KCN (ionic) gives free -:C N: (ambident); attack through C (C–C bond stronger)
⇒ R-X + KCN R-CN (alkyl cyanide)
AgCN is mainly covalent (Ag–C bond) ⇒ only the lone pair on N is free to attack
⇒ R-X + AgCN R-NC (isocyanide) ⇒ A is correct
R calls AgCN ionic ⇒ R is not correct
Answer: (1)