Exams › NEET › Chemistry

Which of the following pairs constitutes a buffer?

1. NaOH and NaCl
2. HNO3 and NH4NO3
3. HCl and KCl
4. HNO2 and NaNO2

Correct answer: HNO2 and NaNO2

Solution

A buffer is formed by a weak acid and its conjugate base or a weak base and its conjugate acid. HNO2 (a weak acid) and NaNO2 (its conjugate base) form a buffer.

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