Question

Give five properties of acids with examples and equations showing the chemical reactions involved.

Answer 1

Properties of acids are as follows:

1. Acids react with metals to form metal salts with evolution of hydrogen gas.
For example, zinc metal reacts with hydrochloric acid to form zinc chloride and hydrogen gas.

$\mathrm{Zn}\left(\mathrm{s}\right)+2HCl\; (aq)\to \mathrm{Z}{\mathrm{nCl}}_2(aq)+{\mathrm{H}}_2(g)$


2. Acids neutralise bases to form a salt and water.
For example, hydrochloric acid reacts with sodium hydroxide (base) to form sodium chloride (salt) and water.

$\mathrm{HCl}\left(\mathrm{aq}\right)+NaOH\; (aq)\to \mathrm{N}\mathrm{aCl\; (aq)}+{\mathrm{H}}_2\mathrm{O\; (l)}$

3. Acids react with metal carbonates (metal hydrogen carbonates) to form carbon dioxide gas, metal salt and water.
For example, sodium carbonate reacts with hydrochloric acid to form sodium chloride, carbon dioxide and water.

${\mathrm{Na}}_2{\mathrm{CO}}_3\left(\mathrm{s}\right)+2\mathrm{HCl\; (aq)}\to 2\mathrm{NaCl\; (aq)}+\mathrm{C}{\mathrm{O}}_2(g)+H_2\mathrm{O\; (l)}$


4. Acids react with metal oxides to form metal salts and water.
For example, calcium oxide reacts with hydrochloric acid to form calcium chloride and water.

$\mathrm{CaO}\left(\mathrm{s}\right)+2HCl\; (aq)\to {CaCl}_2(aq)+H_2\mathrm{O\; (l)}$

5. Acids produce hydrogen ions when dissolved in water.
For example, nitric acid dissolves in water to produce hydrogen ions and nitrate ions.

${\mathrm{HNO}}_3\left(\mathrm{aq}\right)\stackrel{\mathrm{w}\mathrm{a}\mathrm{t}\mathrm{e}\mathrm{r}}{\to }{\mathrm{H}}^{+}(aq)+{N\; O}_3^{-}$