Question

(a) Name a carbonate that does not decompose on heating.

(b) Name a nitrate that produces oxygen as only gas.

(c) Name a compound that produces carbon dioxide on heating.

(d) Name a nitrate that produces brown gas on heating.

Answer 1

(a) A carbonate that does not decompose on heating is Sodium carbonate (NaCO₃)

(b) A nitrate that produces oxygen as only gas is Potassium nitrate (KNO₃)

$$\begin{gathered} 2{\mathrm{KNO}}_3\left(\mathrm{s}\right)\to 2{\mathrm{KNO}}_2\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right) \\ \mathrm{potassium}\mathrm{nitrarte}\mathrm{potassium}\mathrm{nitrite}\mathrm{oxygen} \end{gathered}$$

(c) A compound that produces carbon dioxide on heating is Calcium carbonate (CaCO₃)

$$\begin{gathered} {\mathrm{CaCO}}_3\left(\mathrm{s}\right)\stackrel{∆}{\to }\mathrm{CaO}\left(\mathrm{s}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right) \\ \mathrm{calcium}\mathrm{carbonate}\mathrm{calcium}\mathrm{oxide}\mathrm{carbon}\mathrm{dioxide} \end{gathered}$$

(d) A nitrate that produces brown gas on heating is Lead nitrate [Pb(NO₃)₂]

$$\begin{gathered} 2\mathrm{Pb}{\left({\mathrm{NO}}_3\right)}_2\left(\mathrm{s}\right)\stackrel{∆}{\to }2\mathrm{PbO}\left(\mathrm{s}\right)+4{\mathrm{NO}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right) \\ \mathrm{lead}\mathrm{nitrate}\mathrm{lead}\mathrm{oxide}\mathrm{nitrogen}\mathrm{dioxide}\mathrm{oxygen} \\ (\mathrm{Brown}\mathrm{gas}) \end{gathered}$$