Buffer solution among the following options is :           

1. HNO₂ and NaNO₂           

2. NaOH and NaCl

3. HNO₃ and NH₄NO₃         

4. HCl and KCl

What is [H⁺] in mol/L of a solution that is 0.20 M in CH₃COONa and 0.10 M in CH₃COOH?

(K_a for CH₃COOH = 1.8 x 10^-5)       

1. 3.5x10^-4           

2. 1.1x10^-5

3. 1.8x10^-5           

4. 9.0x10^-6

A physician wishes to prepare a buffer solution at pH=3.58 that efficiently resist changes in pH yet contains only small concetration of the buffering agents. Which one of the following weak acid together with its sodium salt would be best to use ?           [1997]

1. m-chlorobenzoic acid (pK_a = 3.98)

2. p-chlorocinnamic acid (pK_a = 4.41)

3. 2,5-dihydroxy benzoic acid (pK_a = 2.97)

4. Acetoacetic acid (pK_a = 3.58)

In a buffer solution containing equal concentration of B^- and H B, the K_b for B^- is 10^-10. The pH of buffer solution is 

1. 10

2. 7

3. 6

4. 4

The pH of blood is maintained by CO₂ by and H₂CO₃ in the body and chemical constituents of blood. This phenomenon is called:

1. colloidal                           

2. buffer action

3. acidic                               

4. salt balance

Which of the following solution does not act as buffer?

1. H₃PO₄ + NaH₂PO₄

2. Na₂CO₃ + H₂CO₃

3. HCl + NH₄Cl

4. CH₃COOH + CH₃COONa

Which can act as an acidic buffer?

1. Both a and b
2. Both b, and c
3. All are buffer solution
4. Both a, and c

60 ml 1M CH₃COOH is mixed with 20 ml 1 M NaOH then pH of resulting solution will be

(K_a = 1.8 X 10^-5, log1.8 = 0.25)

1. 8.55

2. 4.95

3. 4.45

4. 7.45

What substance could be added to one liter of water to serve as a buffer?

1. One mole of ${\mathrm{CH}}_3{\mathrm{CO}}_2\mathrm{H}$ and 0.5 moles of NaOH

2. One mole of NH₄Cl and one mole of HCl

3. One mole of NH₄OH and one mole of NaOH

4. One mole of ${\mathrm{CH}}_3{\mathrm{CO}}_2\mathrm{H}$ and one mole of HCl

Among the following pairs of solution the one which is not an acidic buffer is 

1. HClO₄ and NaClO₄

2. CH₃COOH and CH₃COONa

3. H₂CO₃ and Na₂CO₃

4. H₃PO₄ and Na₃PO₄