Question

2.76 g of silver carbonate on being strongly heated yields a residue weighing

• A. 2.16 g
• B. 2.48 g
• C. 2.32 g
• D. 2.64 g

Answer 1

Answer: (A)

2.16 g

Answer 2

Unlike other metal carbonates that usually decomposes into metal
oxides liberating carbon dioxide, silver carbonate on heating
decomposes into elemental silver liberating mixture of carbon
dioxide and oxygen gas as : M
$Ag_2CO_3 \, _{\longrightarrow \, \, \, \, }^{Heat} 2Ag (s) + CO_2(g) + \frac{1}{2} O_2(g)$
MW = 276 g \hspace26mm 2 x 108 = 216 g
Hence, 2.76 g of $Ag_2CO_3$ on heating will give
$\frac{216}{216 } \times 2.76$ = 2.16g Ag as residue.