Question

For the given reaction , the major products A and B respectively are :

• A. 1-chloroporpane and Ethyne
• B. 1,2-dichloroethane and ethane
• C. chloroethane and ethane
• D. None of the above

Answer 1

The correct option is B 1,2-dichloroethane and ethane

Addition of halogens:
Halogens like bromine and chlorine add up to alkene to form vicinal dihalides
$CC{l}_4$ is the solvent.

Addition of dihydrogen :

$\text{Alkene}+H_2\stackrel{Ni/Pt/Pd}{\to }\text{Alkane}+\text{heat}$

When nickel is used as a catalyst for addition of dihydrogen, then the reaction is known as Sabatier-Senderens reaction.
So , B is ethane.
The addition of hydrogen is called hydrogenation.The heat released in a hydrogenation reaction is called the heat of hydrogenation i.e. $\Delta H_{HOH}^{\circ }$