Ionic Equilibrium

A solution is prepared by mixing 0.01 mol each of $\ce{H2CO3}$, $\ce{NaHCO3}$, $\ce{Na2CO3}$, and NaOH in 100 mL of water. $p$H of the resulting solution is _____.

[Given: $pK_{a1}$ and $pK_{a2}$ of $\ce{H2CO3}$ are 6.37 and 10.32, respectively; log 2 = 0.30]

Concentration of $\ce{H2SO4}$ and $\ce{Na2SO4}$ in a solution is 1 M and $1.8 \times 10^{-2}$ M, respectively. Molar solubility of $\ce{PbSO4}$ in the same solution is $X \times 10^{-Y}$ M (expressed in scientific notation). The value of $Y$ is ________.

[Given: Solubility product of $\ce{PbSO4}$ $(K_{sp}) = 1.6 \times 10^{-8}$. For $\ce{H2SO4}$, $K_{a1}$ is very large and $K_{a2} = 1.2 \times 10^{-2}$]

The cell potential for the following cell
$$\mathrm{Pt\,|H_2(g)|H^+(aq)\,||\,Cu^{2+}(0.01\ M)|Cu(s)}$$
is 0.576 V at 298 K. The pH of the solution is ______. (Nearest integer)

(Given : $E^\circ_{\mathrm{Cu^{2+}/Cu}}=0.34$ V and $\dfrac{2.303RT}F=0.06$ V)

The $K_{sp}$ for bismuth sulphide ($\mathrm{Bi_2S_3}$) is $1.08\times10^{-73}$. The solubility of $\mathrm{Bi_2S_3}$ in mol L$^{-1}$ at 298 K is

Given below are two statements one is labelled as Assertion A and the other is labelled as Reason R :

Assertion A : The amphoteric nature of water is explained by using Lewis acid/base concept.

Reason R : Water acts as an acid with $\mathrm{NH_3}$ and as a base with $\mathrm{H_2S}$.

In the light of the above statements choose the correct answer from the options given below :

The neutralization occurs when 10 mL of 0.1M acid 'A' is allowed to react with 30 mL of 0.05 M base $\mathrm{M(OH)_2}$. The basicity of the acid 'A' is ______.

[M is a metal]

50 mL of 0.1 M $\mathrm{CH_3COOH}$ is being titrated against 0.1 M NaOH. When 25 mL of NaOH has been added, the pH of the solution will be ______ $\times10^{-2}$. (Nearest integer)

(Given : $\mathrm pK_a(\mathrm{CH_3COOH})=4.76$, $\log2=0.30$, $\log3=0.48$, $\log5=0.69$, $\log7=0.84$, $\log11=1.04$)

pH value of 0.001 M NaOH solution is ______.

The solubility product of a sparingly soluble salt $\mathrm{A_2X_3}$ is $1.1\times10^{-23}$. If specific conductance of the solution is $3\times10^{-5}$ S m$^{-1}$, the limiting molar conductivity of the solution is $x\times10^{-3}$ S m$^2$ mol$^{-1}$. The value of $x$ is ______.

A student needs to prepare a buffer solution of propanoic acid and its sodium salt with pH 4. The ratio of $\dfrac{\left[\mathrm{CH_3CH_2COO^-}\right]}{\left[\mathrm{CH_3CH_2COOH}\right]}$ required to make buffer is ______.

Given : $K_a\left(\mathrm{CH_3CH_2COOH}\right)=1.3\times10^{-5}$

The solubility of AgCl will be maximum in which of the following ?

20 mL of 0.1 M $\mathrm{NH_4OH}$ is mixed with 40 mL of 0.05 M HCl. The pH of the mixture is nearest to :

(Given : $K_b(\mathrm{NH_4OH})=1\times10^{-5}$, log 2 = 0.30, log 3 = 0.48, log 5 = 0.69, log 7 = 0.84, log 11 = 1.04)

$K_{a_1}$, $K_{a_2}$ and $K_{a_3}$ are the respective ionization constants for the following reactions (a), (b), and (c).

(a) $\mathrm{H_2C_2O_4\rightleftharpoons H^++HC_2O_4^-}$

(b) $\mathrm{HC_2O_4^-\rightleftharpoons H^++C_2O_4^{2-}}$

(c) $\mathrm{H_2C_2O_4\rightleftharpoons2H^++C_2O_4^{2-}}$

The relationship between $K_{a_1}$, $K_{a_2}$ and $K_{a_3}$ is given as

In base vs. acid titration, at the end point methyl orange is present as

Class XII students were asked to prepare one litre of buffer solution of pH 8.26 by their Chemistry teacher. The amount of ammonium chloride to be dissolved by the student in 0.2 M ammonia solution to make one litre of the buffer is

(Given: $\mathrm pK_b(\mathrm{NH_3})=4.74$; Molar mass of $\mathrm{NH_3}$ = 17 g mol$^{-1}$; Molar mass of $\mathrm{NH_4Cl}$ = 53.5 g mol$^{-1}$)

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Boric acid is a weak acid.

Reason R: Boric acid is not able to release $\mathrm{H^+}$ ion on its own. It receives $\mathrm{OH^-}$ ion from water and releases $\mathrm{H^+}$ ion.

In the light of the above statements, choose the most appropriate answer from the options given below.

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Phenolphthalein is a pH dependent indicator, remains colourless in acidic solution and gives pink colour in basic medium.

Reason R: Phenolphthalein is a weak acid. It doesn't dissociate in basic medium.

In the light of the above statements, choose the most appropriate answer from the options given below.

At 310 K, the solubility of $\mathrm{CaF_2}$ in water is $2.34\times10^{-3}$ g/100 mL. The solubility product of $\mathrm{CaF_2}$ is ______ $\times10^{-8}$ (mol/L)$^3$. (Give molar mass : $\mathrm{CaF_2}$ = 78 g mol$^{-1}$)

The plot of pH-metric titration of weak base $\mathrm{NH_4OH}$ vs strong acid HCl looks like :

$K_a$ for butyric acid $(\mathrm{C_3H_7COOH})$ is $2\times10^{-5}$. The pH of 0.2 M solution of butyric acid is ______ $\times10^{-1}$. (Nearest integer)

[Given log 2 = 0.30]