Name the following -

(a) Two carbonates that do not produce carbon dioxide on heating.

(b) Two nitrate that does not produce nitrogen dioxide on heating.

(c) A brown gas

(d) A greenish-yellow gas

(e) Gas with rotten egg smell.

(a) Two carbonates that do not produce carbon dioxide on heating = Sodium carbonate (Na₂CO₃), potassium carbonate (K₂CO₃)

• Sodium is a very reactive metal and hence forms a very strong bond with the carbonate ion. Thus Na₂CO₃ does not decompose on heating.
• Potassium carbonate (K₂CO₃) does not decompose on heating.

(b) Two nitrate that does not produce nitrogen dioxide on heating = Sodium nitrate (NaNO₃), potassium nitrate (KNO₃)

• Sodium nitrate (NaNO₃) on heating decomposes into sodium nitrite (NaNO₂) and oxygen gas(O₂).

$$\begin{gathered} 2{\mathrm{NaNO}}_3\left(\mathrm{s}\right)\stackrel{∆}{\to }2{\mathrm{NaNO}}_2\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)(\uparrow ) \\ \mathrm{Sodium}\mathrm{nitrate}\mathrm{Sodium}\mathrm{nitrite}\mathrm{Oxygen} \end{gathered}$$

• Potassium nitrate (KNO₃) on heating

$$\begin{gathered} 2{\mathrm{KNO}}_3\left(\mathrm{s}\right)\stackrel{∆}{\to }2{\mathrm{KNO}}_2\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{s}\right)(\uparrow ) \\ \mathrm{Potassium}\mathrm{nitrate}\mathrm{Potassium}\mathrm{nitrite}\mathrm{Oxygen} \end{gathered}$$

(c) A brown gas = Nitrogen dioxide (NO₂)

(d) A greenish yellow gas = Chlorine (Cl₂)

(e) Gas with rotten egg smell = Hydrogen sulphide (H₂S)