- ASodium acetate and acetic acid in water
- BSodium acetate and hydrochloric acid in water
- CAmmonia and ammonium chloride in water
- ✓$(a) $ and $(c)$ both
Hint: A buffer solution can be prepared by mixing a weak acid or base with the salt of a strong base or strong acid.
Explanation:
Sodium acetate and acetic acid in water can form buffer solution because sodium acetate is a salt of strong acid $NaOH$ and weak acid acetic acid.
$CH _3 COONa + CH _3 COOH$
Sodium acetate and hydrochloric acid in water cannot form a buffer solution because $HCl$ is a strong acid.
Ammonia and ammonium chloride in water can from buffer solution because ammonia is a weak base and ammonium chloride is a salt of ammonia and strong acid $HCl$.
$NH _4 Cl + NH _3$
Ammonia and sodium hydroxide in water cannot form buffer solutions because both are bases.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.


The half-life period is independent of the concentration of zinc at constant $pH$. For the constant concentration of $Zn$, the rate becomes $100$ times when $pH$ is decreased from $3\, to\, 2$. Identify the correct statements $(pH = -\log [H^{+}])$
$(A)$ $\frac{{dx}}{{dt}}\, = k{[Zn]^0}{[{H^ + }]^2}$
$(B)$ $\frac{{dx}}{{dt}}\, = k{[Zn]}{[{H^ + }]^2}$
$(C)$ Rate is not affected if the concentraton of zinc is made four times and that of $H^+$ ion is halved.
$(D)$ Rate becomes four times if the concentration of $H^+$ ion is doubled at constant $Zn$ concentration