Question

How are salts classified? Describe giving one example of each.

Answer 1

1. Salts: Salts are the product of a neutralization reaction between an acid and a base.
2. Salts are classified into three types:
   1. Neutral salts
   2. Acidic salt
   3. Basic salt

Neutral salts:

• The salt obtained by the complete replacement of ionisable hydrogen atoms in an acid molecule with metal ions is called neutral salt.
• This type of salt is generally formed due to a reaction between a strong acid and a strong base.
• For example, Sodium chloride is formed by the reaction of Sodium hydroxide and Hydrochloric acid.

Acidic salt:

• The salt obtained by partial replacement of ionisable hydrogen atoms in an acid molecule with metal ions is called an acid salt.
• This type of salt is generally formed due to a reaction between a strong acid and a weak base.
• For example, when sulphuric acid reacts with sodium hydroxide to give sodium hydrogen sulphate.
• $$\begin{gathered} {\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)+\mathrm{NaOH}\left(\mathrm{aq}\right)\to {\mathrm{NaHSO}}_4\left(\mathrm{aq}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Sulphuric}\mathrm{Sodium}\mathrm{Sodium}\mathrm{water} \\ \mathrm{acid}\mathrm{hydroxide}\mathrm{hydrogen} \\ \left(\mathrm{acid}\right)\left(\mathrm{Base}\right)\mathrm{sulphate} \\ \left(\mathrm{salt}\right) \end{gathered}$$

Basic salt:

• The salt which contains one or more hydroxyl groups(coming from the base) along with the anion coming from the acid is called a basic salt.
• This type of salt is generally formed due to a reaction between a weak acid and a strong base.
• For example, when Calcium hydroxide reacts with Hydrochloric acid to give Calcium hydrogen chloride.
• $$\begin{gathered} \mathrm{Ca}{\left(\mathrm{OH}\right)}_2\left(\mathrm{aq}\right)+\mathrm{HCl}\left(\mathrm{aq}\right)\to \mathrm{Ca}\left(\mathrm{OH}\right)\mathrm{Cl}\left(\mathrm{aq}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \\ \mathrm{Calcium}\mathrm{Hydrochloric}\mathrm{Calcium}\mathrm{hydroxy}\mathrm{water} \\ \mathrm{hydroxide}\mathrm{acid}\mathrm{chloride} \\ \left(\mathrm{Base}\right)\left(\mathrm{Acid}\right)\left(\mathrm{Basic}\mathrm{salt}\right) \end{gathered}$$