$CrO_4^{2-}$ (yellow) changes to $Cr_2O_7^{2-}$ (orange) in $pH = x$ and vice-versa in $pH = y$. Hence,$x$ and $y$ are

For a $0.1 \, M$ aqueous solution of a weak acid undergoing $2\%$ ionization,the concentration of $[H^{+}]$ and $[OH]^{-}$ will be respectively: (Ionic product of water $= 1 \times 10^{-14}$)

$2.5 \ mL$ of $\frac{2}{5} \ M$ weak monoacidic base ($K_{b} = 1 \times 10^{-12}$ at $25^{\circ} C$) is titrated with $\frac{2}{15} \ M \ HCl$ in water at $25^{\circ} C$. The concentration of $H^{+}$ at equivalence point is ($K_W = 1 \times 10^{-14}$ at $25^{\circ} C$).

The initial rate of hydrolysis of methyl acetate $(1 \ M)$ by a weak acid $(HA, 1 \ M)$ is $1/100$th of that of a strong acid $(HX, 1 \ M)$ at $25^{\circ} C$. The $K_a$ of $HA$ is:

Given below are two statements :
Statement $I$ : Aqueous solution of ammonium carbonate is basic.
Statement $II$ : Acidic/basic nature of salt solution of a salt of weak acid and weak base depends on $K_a$ and $K_b$ value of acid and the base forming it.
In the light of the above statements,choose the most appropriate answer from the options given below :

$A$ sample of $Na_2CO_3 \cdot H_2O$ weighing $0.62 \ g$ is added to $100 \ mL$ of $0.1 \ N \ (NH_4)_2SO_4$ solution. What will be the nature of the resulting solution?