Question

Fusion of AgCl with $N{a_2}C{O_3}$ gives:
(A) $A{g_2}C{O_3}$
(B) Silver carbide
(C) Ag
(D) $A{g_2}$

Answer 1

Hint : Silver chloride, AgCl, is a white crystalline solid that is very less soluble in water. It can be prepared by the reaction of silver nitrate with sodium chloride. Sodium carbonate, $N{a_2}C{O_3}$ , also known as washing soda, is a white solid and is water soluble. The reaction between AgCl and $N{a_2}C{O_3}$ is a double displacement reaction.

Complete Step By Step Answer:
Silver chloride (AgCl) on reacting with sodium carbonate ( $N{a_2}C{O_3}$ ) initially forms silver carbonate ( $A{g_2}C{O_3}$ ) and sodium chloride (NaCl). But the pale yellow crystals of silver carbonate thus formed is unstable and thus $A{g_2}C{O_3}$ decomposes into elemental silver (Ag), carbon dioxide and oxygen via the formation of silver oxide ( $A{g_2}O$ ). And therefore, we do not get $A{g_2}C{O_3}$ as the end product. Both $A{g_2}C{O_3}$ and $A{g_2}O$ are thermally unstable and the reaction is taking place at $850 - {900^ \circ }C$ .
Above reaction is as follows:
$2N{a_2}C{O_3} + 4AgCl \to 4Ag + 2C{O_2} + 4NaCl + {O_2}$
The reaction of fusion of AgCl with sodium carbonate thus gives free silver, sodium chloride, with the liberation of carbon dioxide and oxygen. Silver is white, soft, lustrous metal with high thermal and electrical conductivity. It is a rather unreactive metal and does not react with air and even heat. It is considered as a noble metal.
Therefore, the correct option is (C) Ag.

Note :
Silver carbide or silver acetylide $(A{g_2}{C_2})$ is formed when acetylene gas is passed through a silver nitrate solution. It is a heat and shock sensitive explosive.
$2AgN{O_3}(aq) + {C_2}{H_2}(g)\, \to \,A{g_2}{C_2}(s) + 2HN{O_3}(aq)$
Silver carbonate ( $A{g_2}C{O_3}$ ) is prepared by the reaction between aqueous solutions of silver nitrate and sodium carbonate. It can be used as a reagent in various organic reactions.
$2AgN{O_3}(aq) + N{a_2}C{O_3}(aq) \to A{g_2}C{O_3}(s) + 2NaN{O_3}(aq)$
$A{g_2}$ is silver $( + 1)$ cation.