Question

Which of the following aqueous solutions are good buffer systems?

 

• 0.21 M perchloric acid + 0.22 M potassium perchlorate 

• 0.14 M potassium hypochlorite + 0.20 M hypochlorous acid 

• 0.38 M acetic acid + 0.30 M potassium acetate 

• 0.28 M ammonium bromide+ 0.36 M ammonia 

• 0.11 M hydrofluoric acid + 0.13 M potassium fluoride

Answer 1

acidic buffer is formed by weak acid and its conjugate base

basic buffer is formed by weak base and its conjugate acid

Option 1:

HClO4 is acid here which is string acid.

So, it will not form buffer

Option 2:

HClO is weak acid and ClO- is its conjugate base.

So, they will form buffer

Option 3:

CH3COOH is weak acid and CH3COO- is its conjugate base.

So, they will form buffer

Option 4:

NH3 is weak base and NH4+ is its conjugate acid.

So, they will form buffer

Option 5:

HF is weak acid and F- is its conjugate base.

So, they will form buffer

Answer: option 2, 3, 4, 5