Buffer

The following pair constitutes a buffer is:

1. $HN{O}_2$ $and$ $NaN{O}_2$

2. $NaOH$ $and$ $NaCl$

3. $HN{O}_3$ $and$ $N{H}_{4}N{O}_3$

4. $HCl$ $and$ $KCl$

Calculate the hydrogen ion concentration, [ ] (in ), of a buffer solution prepared by mixing acetic acid ( ) and sodium acetate ( ), given that the acid dissociation constant ( ) for acetic acid is :

1.
2.
3.
4. ${\mathrm{}}^{}$

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

A buffer solution is prepared in which the concentration of NH₃ is 0.30 M and the concentration of $N{H}_4^{+\hspace{0.17em}}$ is 0.20 M. If the equilibrium constant, K_b for NH₃ equals 1.8\times 10^–5, then what is the pH of this solution?
(log 1.8 = 0.25; log 0.67 = –0.176)

1. 9.43
2. 11.72
3. 8.73
4. 9.08

Buffer solutions have constant acidity and alkalinity because:

Which one of the following pairs of solutions is not an acidic buffer?

1. ${\mathrm{HClO}}_4$ $\mathrm{and}$ ${\mathrm{NaClO}}_4$
2. ${\mathrm{CH}}_3\mathrm{COOH}$ $\mathrm{and}$ ${\mathrm{CH}}_3\mathrm{COONa}$
3. ${\mathrm{H}}_2{\mathrm{CO}}_3$ $\mathrm{and}$ ${\mathrm{Na}}_2{\mathrm{CO}}_3$
4. ${\mathrm{H}}_3{\mathrm{PO}}_4$ $\mathrm{and}$ ${\mathrm{Na}}_3{\mathrm{PO}}_4$

Which composition will make the basic buffer?