If small amount of an acid or alkali is added to a buffer solution, it converts them into unionised acid or base. Thus, its pH remains unaffected or in other words its acidity/alkalinity remains constant. e.g., H3O++A−⇌H2O+HA−OH+HA⟶H2O+A− If acid is added, it reacts with A−to form undissociated HA. Similarly, if base/alkali is added, OH−combines with HA to give H2O and A−and thus, maintains the acidity/ alkalinity of buffer solution.
Buffer solutions have constant acidity and alkalinity because
NEET UG 2012 — Chemistry Physical Chemistry
2012mcqhard
Buffer solutions have constant acidity and alkalinity because
Official previous-year question
Held on 30 Apr 2012 · Verified 9 Jul 2026.
Options
- A
these give unionised acid or base on reaction with added acid or alkali
- B
acids and alkalies in these solutions are shielded from attack by other ions
- C
they have large excess of H+or OH−ions
- D
they have fixed value of pH
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