Question

Statement 1: Reduction of but-2-yne by Na/liq. $N{{H}_{3}}$ gives trans but-2-ene.
Statement 2: It is an example of anti-addition.
A. Statement-1 is true, statement-2 is true and statement-2 is the correct explanation for the statement-1.
B. Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for the statement-1.
C. Statement-1 is true, statement-2 is false
D. Statement-1 is false, statement-2 is true

Answer 1

Hint: The process of addition of electrons or addition of hydrogens is called reduction. The structure of but-2-yne is as follows.

There is a triple bond at the center of the molecule.

Complete step by step answer:
- In the question it is asked to find the correct statements among the given two statements.
- Generally the compound which contains double or rippled bonds undergoes additional reactions and forms saturated compounds as the products.
- Generally reduction reactions are going to carry out the presence of hydrogen in the presence of Lindlar catalysts.
- In the presence of the Lindlar catalyst the product formed by the but-2-yne is cis -2-butene.
- But in the question it is given that but-2-yne is going to react with liquid ammonia in the presence of sodium.
- The chemical reaction of but-2-yne with hydrogen Lindlar catalyst and the sodium liquid ammonia is as follows.

- Therefore by observing the given statements
Statement 1: Reduction of but-2-yne by Na/liq. $N{{H}_{3}}$ gives trans but-2-ene.
Statement 2: It is an example of anti-addition.
Both the statements are correct and statement 2 is a right explanation form statement 1.

Therefore the correct option is option A.

Note: In the presence of sodium and liquid ammonia anti addition takes place and leads to the formation of trans-2-butene as the product. Linlard catalyst favors the formation of the cis but-2-ene as the product.