Acidic, Basic and Neutral Salts
This is part of the HSC Chemistry course under the topic Quantitative Analysis.
HSC Chemistry Syllabus
write ionic equations to represent the dissociation of acids and bases in water, conjugate acid/base pairs in solution and amphiprotic nature of some salts, for example:
What are acidic, basic and neutral salts?
What are Salts?
Salts are ionic compounds produced from an acid-base reaction.
Many salts, despite being neutrally charged, produce acidic and basic solutions when dissolved in water.
The properties of acidic and basic salts can be understood using the Brønsted-Lowry acid/base theory.
- Ammonium nitrate
- Ammonium sulfate
- Potassium acetate
- Sodium fluoride
- Sodium hypochlorite
- Sodium citrate
Neutral salts are neutral because they contain neither of conjugate acids of weak bases or conjugate bases of weak bases.
Neutral salts are typically formed from neutralisation between strong acids and strong bases.
An example of a neutral salt is sodium chloride, which is formed from the neutralisation between hydrochloric acid and sodium hydroxide:
$$HCl(aq) + NaOH(aq) \rightarrow NaCl(aq) + H_2O(l)$$
Sodium and chloride ions are both spectator ions. Chloride ions are unable to accept protons from water because they are the conjugate base of hydrochloric acid which is a strong acid. Strong acids like HCl completely dissociate in water:
$$HCl(aq) \rightarrow H^+(aq) + Cl^-(aq)$$
Sometimes a neutral salt can be formed from the neutralisation between a strong acid and weak base. For example, the reaction between hydrochloric acid and sodium carbonate (weak base) produces sodium chloride:
$$HCl(aq) + Na_2CO_3(aq) \rightarrow NaCl(aq) + H_2O(l) + CO_2(g)$$
Other examples of neutral salts include:
- Potassium chloride
- Sodium nitrate
- Potassium nitrate