Question

During extraction of silver from silver glance by cyanide process, $N{{a}_{2}}[Zn{{(CN)}_{4}}]$ becomes soluble and Ag is precipitated.
If the statement is true press 1, else press 0

Answer 1

Hint: Silver is extracted from the ore-argentite. The process of extraction of silver is called a cyanide process as sodium cyanide solution is used. The ore is crushed, concentrated, and then treated with sodium cyanide solution.

Complete Step by step solution:
To understand if the above statement is correct or not it is important to understand the entire procedure of extraction of silver from silver glance by the cyanide process.

The concentrated ore that is argentite is treated with an aqueous solution of sodium cyanide and the air current passes through it. The argentite ore dissolves in sodium cyanide and forms \[Na[Ag(C{{N}_{2}}]\].
Let’s see the reaction:
               \[A{{g}_{2}}S+4NaCN\to 2Na[Ag(C{{N}_{2}}]+N{{a}_{2}}S\]
The above reaction is reversible therefore the byproduct passed to oxidize \[N{{a}_{2}}S\text{ }\!\!~\!\!\text{ }to\text{ }\!\!~\!\!\text{ }N{{a}_{2}}S{{O}_{4}}~\] such that the equilibrium shifts towards the product.
\[N{{a}_{2}}S+{{O}_{2}}~\to ~~N{{a}_{2}}S{{O}_{4}}\]
The solution is undergoing a filtration process and the filtrate containing \[Na[Ag(C{{N}_{2}}]\] is used in the recovery of silver metal.
The solution obtained is reacted with zinc in which zinc displaces silver from its complex.
\[Zn+2Na\text{ }\!\!~\!\!\text{ }[Ag{{\left( CN \right)}_{2}}]~\to ~N{{a}_{2}}[Zn{{\left( CN \right)}_{4}}]+2Ag\downarrow \]
$N{{a}_{2}}[Zn{{(CN)}_{4}}]$ is soluble and hence it is easy to separate $N{{a}_{2}}[Zn{{(CN)}_{4}}]$ from precipitated silver metal.
The precipitate of silver metal is collected, washed, and fused to get a compact mass of silver metal.
According to the above mentioned process, we conclude that the given statement is true. Hence press 1.

Note: Argentite and galena are two important ores of silver. The molecular formula for argentite is \[~A{{g}_{2}}S\] and for galena is \[PbS\]. Galena is also called lead glance and it is the most important ore of lead and an important source of silver.