An aqueous solution of sodium chloride is prepared in distilled water. The pH of this solution is :

Sodium chloride ($\mathrm{NaCl}$) is a neutral salt formed by the neutralization reaction of a strong acid (hydrochloric acid, $\mathrm{HCl}$) and a strong base (sodium hydroxide, $\mathrm{NaOH}$):

$$\mathrm{NaOH(aq) + HCl(aq) \rightarrow NaCl(aq) + H_2O(l)}$$

Since both the parent acid and parent base are strong, the resulting salt solution is completely neutral and has a pH of exactly $7$ at room temperature.

• Why Option C is correct: A pH of $7$ represents a neutral solution, which is characteristic of an aqueous solution of a neutral salt like $\mathrm{NaCl}$.
• Why Options A, B, and D are incorrect: A pH of $6$ (Option A) or $3$ (Option D) represents acidic solutions, while a pH of $8$ (Option B) represents a basic solution. $\mathrm{NaCl}$ does not undergo hydrolysis to produce excess hydronium or hydroxide ions.