Question

A neutral oxide that does not react with an acid or a base to give salt and water

• A. Iron
• B. Carbonic acid
• C. Hydrogen
• D. Oxygen
• E. Carbon monoxide

Answer 1

The correct option is E

Carbon monoxide

The explanation for the correct answer

(e) Carbon monoxide

Carbon monoxide is a neutral oxide.

Neutral oxides show neither basic nor acidic properties and hence do not form salts when reacted with acids or bases.

The explanation for the incorrect answer

(a) Iron

• Iron oxide reacts with acid or base to form salt and water.
• Example: $$\begin{gathered} {\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+6\mathrm{HCl}\left(\mathrm{aq}\right)\to 2{\mathrm{FeCl}}_3\left(\mathrm{aq}\right)+3{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Ferric}\mathrm{oxide}\mathrm{Hydrochloric}\mathrm{acid}\mathrm{Ferric}\mathrm{chloride}\mathrm{Water} \end{gathered}$$

(b) Carbonic acid

• Carbonic acid reacts with a base to form sodium bicarbonate and water.
• Example: $$\begin{gathered} {\mathrm{H}}_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)+\mathrm{NaOH}\left(\mathrm{aq}\right)\to {\mathrm{NaHCO}}_3\left(\mathrm{aq}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Carbonic}\mathrm{acid}\mathrm{Sodium}\mathrm{hydroxide}\mathrm{Sodium}\mathrm{bicarbonate}\mathrm{Water} \end{gathered}$$

(c) Hydrogen

• Hydrogen reacts with a base to form salt and water.
• Example: $$\begin{gathered} \mathrm{HCl}\left(\mathrm{aq}\right)+\mathrm{NaOH}\left(\mathrm{s}\right)\to \mathrm{NaCl}\left(\mathrm{s}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Hydrochloric}\mathrm{acid}\mathrm{Sodium}\mathrm{hydroxide}\mathrm{Sodium}\mathrm{chloride}\mathrm{Water} \end{gathered}$$

(d) Oxygen

• Calcium oxide reacts with hydrochloric acid to form calcium chloride salt and water.
• Example: $$\begin{gathered} \mathrm{CaO}\left(\mathrm{s}\right)+2\mathrm{HCl}\left(\mathrm{aq}\right)\to {\mathrm{CaCl}}_2\left(\mathrm{s}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Calcium}\mathrm{oxide}\mathrm{Hydrochloric}\mathrm{acid}\mathrm{Calcium}\mathrm{chloride}\mathrm{Water} \end{gathered}$$

Therefore, the correct option is (e)