Which pair of compounds will form a buffer in aqueous solution? HCN and NaCN HCl and NaOH NaCN and NaOH HCN and HCl HCl and NaCl NaCN and KCN.
Concepts and reason
The concept used to solve this problem is that a buffer is formed by the combination of a weak acid and its salt of a strong acid or by the combination of a weak base and its salt of strong acid.
Fundamentals
A buffer solution is a solution that resists change in pH on addition of a strong base or a strong acid.
Buffer solutions are of 2 types:
Acidic buffer- This is formed by a weak acid and its salt of strong base.
Basic buffer- This is formed by a weak base and its salt of strong acid.
Answer:
Part A
HCN and NaCN form a buffer in aqueous Solution.
Part B
HCl and NaOH don’t form a buffer in aqueous Solution.
Part C
NaOH and NaCN will not form a buffer in aqueous Solution.
Part D
HCl and HCN don’t form a buffer in aqueous Solution.
Part E
HCl and NaCl will not form a buffer in aqueous Solution.
Part F
NaCN and KCN don’t form a buffer in aqueous Solution.