Question

$36.4g$ of $1$, $1$, $2$, $2$-tetrachloropropane was heated with zinc dust and the product was bubbled through ammonical $AgN{O}_3$. What is the weight of precipitate obtained?

• A. $30.0g$
• B. $29.4g$
• C. $28.0g$
• D. $25.7g$

Answer 1

Answer: (B)

The dehalogenation of vicinal tetrahaloalkane gives alkynes. It is done by heating the compound with Zn dust.


$\because 182g$ of tetrachloro alkane gives $147g$ of $ppt$.
$\therefore 36.4g$ of tetrachloro alkane gives $\frac{147\times 36.4}{182}$
$=29.4g$ of precipitate