2021 · Q71
Which one of the following substances, when added to water, will not change the pH ?
General ScienceChemistry
- ANaHCO_3
- BNH_4CI
- CNa_2CO_3
- DNaCI
Explanation
Sodium chloride is the salt of a strong acid (HCl) and a strong base (NaOH); it does not hydrolyse in water, so the solution stays neutral and the pH is unchanged. NaHCO₃ and Na₂CO₃ hydrolyse to give basic solutions, while NH₄Cl gives an acidic solution. Hence (D) NaCl will not change the pH.