Equilibrium practice · Medium

The $K_{\mathrm{sp}}$ of $\mathrm{Ag}_2 \mathrm{CrO}_4=1.2 \times 10^{-11}.$ What concentration of $\mathrm{Ag}^{+}$ ion in aqueous solution will just fail to give a precipitate of $\mathrm{Ag}_2 \mathrm{CrO}_4$ with a solution in which $\left[\mathrm{CrO}_4^{-2}\right]=3 \times 10^{-4} \mathrm{M}?$

Statement I : For the reaction, $A + B \rightleftharpoons C;\,\,{K_C} = 2$
If we start with 1 mole each of A, B and C in 5 L flask, then at equilibrium, molar concentration of A and B increases and that of B decreases
Statement II : Reaction quotient $Q > {K_C}$ with given quantity of A, B and C, hence reaction is reversed.

A saturated solution prepared by dissolved $\mathrm{Ca}{\mathrm{F}_2}\left( s \right)$ in water, has $\left[ {\mathrm{C}{\mathrm{a}^{2 + }}} \right] = 3.3 \times {10^{ - 4}}$ M. What is the ${K_{\mathrm{sp}}}$ of $\mathrm{Ca}{\mathrm{F}_2}$?

The total number of different kind of buffers obtained during the titration of ${\mathrm{H}_3}\mathrm{P}{\mathrm{O}_4}$ with $\mathrm{NaOH}$ are:

The total number of different kind of buffers obtained during the titration of ${\mathrm{H}_3}\mathrm{P}{\mathrm{O}_4}$ with $\mathrm{NaOH}$ are:

STATEMENT I : $\mathrm{pH}$ of a aqueous solution of acetic acid remains unchanged on the addition of sodium acetate.

STATEMENT II : Dissociation of acetic acid is increased by the addition of sodium acetate due to common ion effect.

An aqueous solution contains $\mathrm{N}{\mathrm{i}^{2 + }},\mathrm{C}{\mathrm{o}^{2 + }}\;\mathrm{and}\;\mathrm{ P}{\mathrm{b}^{2 + }}$ ions at equal concentrations. The solubility product of $\mathrm{NiS},\mathrm{PbS}\;\mathrm{ and }\;\mathrm{CoS}$ in water at $25^\circ C$ are $1.4 \times {10^{ - 24}},\;3.4 \times {10^{ - 28}}\;\mathrm{and}\;3 \times {10^{ - 26}}$, respectively. Indicate which of these ions will be precipitated first and last when sulphide concentration is progressively increased from zero?

Assertion : Mixture of ${CH}_3 {COOH}$ and ${CH}_3 {COONH}_4$ is an example of acidic buffer.

Reason: Acidic buffer contains equimolar mixture of a weak acid and its salt with weak base.

The solubility of $\mathrm{CaCO}_3$ is $7 \mathrm{~mg/litre}.$ Calculate the solubility product of $\mathrm{BaCO}_3$ from this information and from the fact that when $\mathrm{Na}_2 \mathrm{CO}_3$ is added slowly to a solution containing equimolar concentration of $\mathrm{Ca}^{2+}$ and $\mathrm{Ba}^{2+},$ no precipitate of $\mathrm{CaCO}_3$ is formed until $90 \%$ of $\mathrm{Ba}^{2+}$ has been precipitated as $\mathrm{BaCO}_3.$

$\mathrm{pH}$ of an acidic buffer is 7 and $\mathrm{pKa}$ is 5 then the ratio of $\frac{[\text { salt }]}{[\text { Acid }]}$ is:-

A 0.2 molar solution of formic acid is $3.2 \%$ ionised, its ionisation constant is

Assertion :- For the reaction $A \rightleftharpoons B + C + D$ at equilibrium state $[A]=[B]=[C]=3 \times 10^{-4} \mathrm{M}$ and equilibrium constant is $3 \times 10^{-4}.$
Reason :- Given reaction is exothermic.

Statement I : For the equilibrium $H_{2(g)}+I_{2(g)} \rightleftharpoons 2 H I_{(g)}, K_C$ is doubled if volume of the vessel is reduced to half its initial volume.
Statement II : Decrease in volume proportionately decrease the concentrations of both reactants & products.

The values of $\mathrm{K}_{\mathrm{sp}}$ of $\mathrm{CaCO}_3$ and $\mathrm{CaC}_2 \mathrm{O}_4$ are $4.7 \times 10^{-9}$ and $1.3 \times 10^{-9}$ respectively at $25^{\circ} \mathrm{C}$. If the mixture of these two is washed with water, what is the concentration of $\mathrm{Ca}^{2+}$ ions in water?

The pH of an aqueous solution having hydroxide ion concentration as $1 \times {10^{ - 5}}$ is

Find change in $\mathrm{pH}$ of water when $1 \mathrm{~mL}$ of $10^{-3} \mathrm{M}$ $\mathrm{KOH}$ is added to $99 \mathrm{~mL}$ of $\mathrm{H}_2 \mathrm{O}$ at $25^{\circ} \mathrm{C}$.

Which statement is false? (Assume complete dissociation in each case)

Assertion (A): At an equilibrium $\mathrm{A}(\mathrm{g})+2 \mathrm{B}(\mathrm{g}) \rightleftharpoons \mathrm{C}(\mathrm{g})$ if substantial amount of water is added to the mixture and stated that only $\mathrm{A}(\mathrm{g})$ gets dissolved to a certain extent in water then equilibrium shifts towards forward direction.

Reason (R): On decreasing the volume of reaction mixture and keeping rest of things same the equilibrium shifts to a direction having more number of gaseous molecules.

The $\mathrm{pH}$ of a buffer solution containing $2.0 \mathrm{~mol}$ per litre $\mathrm{CH}_3 \mathrm{COONa}$ and $1.5 \mathrm{~mol}$ per litre $\mathrm{CH}_3 \mathrm{COOH}$ is: $\left(K_a\right.$ for acetic acid is $1.8 \times 10^{-5}$ )

The ${pK}_{{b}}$ value of ammonium hydroxide is 4.75. An aqueous solution of ammonium hydroxide is titrated with ${HCl}$. The ${pH}$ of the solution at the point where half of ammonium hydroxide has been neutralised will be

For the gaseous phase reaction, $2NO\leftrightharpoons{N_2} + \mathrm{ }{O_2}$, $\Delta {H^ \circ } = \mathrm{ } - \mathrm{ }43.5\mathrm{ }\;k\;cal\mathrm{ }\;mo{l^{ - 1}},$  which statement is correct for, ${N_2}\left( g \right)\mathrm{ } + \mathrm{ }{O_2}\left( g \right)\mathrm{ }\leftrightharpoons\mathrm{ }2NO\left( g \right)?$

For the reaction $A({~g})+3 B({~g}) \rightleftharpoons 2 C({~g})$ at $27^{\circ} {C}, 2$ moles of $A, 4$ moles of $B$ and 6 moles of $C$ are present in 2 litre vessel. If $K_c$ for the reaction is 1.2 , the reaction will proceed in :

Consider the reactions
(i) $\mathrm{CO}(g)+\mathrm{H}_2 \mathrm{O}(g) \stackrel{K_1}{\rightleftharpoons} \mathrm{CO}_2(g)+\mathrm{H}_2(g)$
(ii) $\mathrm{CH}_4(g)+\mathrm{H}_2 \mathrm{O}(g) \stackrel{K_2}{\rightleftharpoons} \mathrm{CO}(g)+3 \mathrm{H}_2(g)$

(iii) $\mathrm{CH}_4(g)+2 \mathrm{H}_2 \mathrm{O}(g) \stackrel{K_3}{\rightleftharpoons} \mathrm{CO}_2(g)+4 \mathrm{H}_2(g)$

Which of the following is correct relation?

Of the following which change will shift the reaction towards the product?

${I}_2({~g}) \rightleftharpoons 2 {I}({g}), \Delta H_r^0(298 {~K})=+150 {~kJ}$

Which of the following ions can exist in solution?

In a $5.76 \mathrm{~L}$ vessel, 0.5 moles of $\mathrm{H}_2$ gas and 0.5 moles of $\mathrm{I}_2$ vapours are allowed to react to form $\mathrm{HI}(\mathrm{g})$ at $447^{\circ} \mathrm{C},$ then the total pressure of gases at equilibrium would be $(R=0.08 \mathrm{~L}-\mathrm{atm} / \mathrm{K}-\mathrm{mol})$

If solubility of gas 'x' in water is 0.5 g/L at 1 bar pressure then solubility at 4 bar pressure will be

Statement I 1 mole $A(g)$ and 1 mole $B(g)$ give 0.5 mole of $C(g)$ and 0.5 mole $D(g)$ at equilibrium.

$A(g)+B(g) \rightleftharpoons C(g)+D(g)$

On taking 2 moles each of $A(g)$ and $B(g)$, percentage dissociation $A(g)$ and $B(g)$ is also doubled.

Statement II Equilibrium constant, $K_c=1$

Determine the degree of dissociation of $0.05 \mathrm{~M} \, {NH}_4 {OH}$ at $25^{\circ} \mathrm{C}$ in a solution of $\mathrm{pH}=10$.

In $2 \mathrm{HI}(\mathrm{g}) \rightleftharpoons \mathrm{H}_2(\mathrm{g})+\mathrm{I}_2(\mathrm{g}), 2$ mole $\mathrm{HI}, 4 \mathrm{~mole}\, \mathrm{H}_2$ and 4 mole of $\mathrm{I}_2$ are found at equilibrium. If some hydrogen is now introduced into the container such that at equilibrium concentration of $\mathrm{HI}$ and $\mathrm{I}_2$ become equal. Find the Number of mole of $\mathrm{H}_2$ added.