Question

Which of the following salts has the highest pH in water?

• A. KCl
• B. Na$_2$CO$_3$
• C. NaCl
• D. CuSO$_4$

Hint:

Salts of strong acids and strong bases, like NaCl, do not alter the pH of water significantly. However, salts of weak acids or weak bases can make the solution acidic or basic.

Answer 1

The Correct Option is C

The pH of a salt in water depends on the ions it dissociates into. Sodium chloride (NaCl) is a neutral salt because it is derived from a strong acid (HCl) and a strong base (NaOH). Thus, when NaCl dissolves in water, it does not affect the pH significantly, resulting in a neutral pH of 7. On the other hand, salts like sodium carbonate (Na$_2$CO$_3$) are basic, and salts like copper sulfate (CuSO$_4$) are acidic. Therefore, NaCl has the highest pH, which is neutral.