Which of the following decomposition equations are correct?
A. \(\mathrm{Ag}_2 \mathrm{CO}_{3(\mathrm{~s})} \rightarrow \mathrm{Ag}_2 \mathrm{O}_{(\mathrm{s})}+\mathrm{CO}_{2(\mathrm{~g})}\) B. \(2 \mathrm{PbCO}_{3(\mathrm{~s})} \rightarrow 2 \mathrm{~Pb}_{(\mathrm{s})}+2 \mathrm{CO}_{2(\mathrm{~g})}+\mathrm{O}_{2(\mathrm{~g})}\) C. \(2 \mathrm{NaNO}_{3(s)} \rightarrow 2 \mathrm{NaNO}_{2(\mathrm{~s})}+\mathrm{O}_{2(\mathrm{~g})}\) D. \(\mathrm{Ag}_2 \mathrm{CO}_{3(s)} \rightarrow \mathrm{AgO}_{(\mathrm{s})}+\mathrm{CO}_{2(\mathrm{~g})}\)
Correct Answer: D
Explanation
The carbonates of \(\mathrm{Hg}, \mathrm{Ag}\) and Au decompose into the parent metals, \(\mathrm{CO}_2\) and \(\mathrm{O}_2\) \(2 \mathrm{Ag}_2 \mathrm{CO}_3 \underset{\Delta}{\longrightarrow} 4 \mathrm{Ag}+2 \mathrm{CO}_2+\mathrm{O}_2\) The carbonates of metals like calcium, magnesium, copper, zinc etC. decompose into the corresponding metal oxides and \(\mathrm{CO}_2\) \(\mathrm{PbCO}_3 \underset{\Delta}{\longrightarrow} \mathrm{PbO}+\mathrm{CO}_2\) Trioxonitrates \((V)\) of potassium and sodium decompose to give dioxonitrate (III) and \(\mathrm{O}_2\). \(2 \mathrm{NaNO}_3 \rightarrow 2 \mathrm{NaNO}_2+\mathrm{O}_2\) \(2 \mathrm{KNO}_3 \underset{\Delta}{\longrightarrow} 2 \mathrm{KNO}_2+\mathrm{O}_2\)
