Equilibrium practice · Medium

The correct order of increasing $\left[ {{\mathrm{H}_3}{\mathrm{O}^ + }} \right]$ in the following aqueous solutions is:

For the following gaseous equilibria $\mathrm{X}, \mathrm{Y}$ and $\mathrm{Z}$ at $300 \mathrm{~K}$

$\mathrm{X}: 2{SO}_2+{O}_2 \rightleftharpoons {SO}_3$

$\begin{aligned} & \text {Y}: {PCl}_5 \rightleftharpoons {PCl}_3+{Cl}_2 \\ & \mathrm{Z}: 2 {HI} \rightleftharpoons {H}_2+{I}_2 \end{aligned}$

ratio of $K_p$ and $K_C$ in the increasing order is

Assertion (A): Higher order ionisation constant $\left(K_{a_2}, K_{a_3}\right)$ are smaller than the lower order ionisation constant $\left(K_{a_1}\right)$ of a polyprotic acid.

Reason (R): It is more difficult to remove a positively charged proton from a negative ion due to Coulombic forces.

(A): Water acts as leveling solvent for various acids.

(R): Levelling effect of water is due to its high dielectric constant and strong proton accepting tendency.

Nucleophiles are:

The $\mathrm{pH}$ of ${10^{ - 8}}\mathrm{M\; HCl}$ solution is

In the problem 13, the dissociation constant of acid is :

$\mathrm{CuSO}_4 \cdot 5 \mathrm{H}_2 \mathrm{O}(\mathrm{s}) \rightleftharpoons \mathrm{CuSO}_4 \cdot 3 \mathrm{H}_2 \mathrm{O}(\mathrm{s})+2 \mathrm{H}_2 \mathrm{O}(\mathrm{g}), K_{\mathrm{P}}$ for this equilibrium is $1.0 \times 10^{-4} \mathrm{~atm}^2$ at $25^{\circ} \mathrm{C}$. What is the maximum pressure of water vapour (moisture) in the atmosphere, below which the pentahydrate is efflorescent?

Assuming 100% ionisation which will have maximum pH

Statement I: The solubility of gases always increases with inctease in pressure

Statement II : High prespure favours the change where volume decreases

Assertion :- The pH of an aqueous solution of acetic acid remains unchanged on the addition of sodium acetate.

Reason :- The ionization of acetic acid is suppressed by the addition of sodium acetate.

If $\mathrm{pK}_{\mathrm{b}}$ for fluoride ion at $25^{\circ} \mathrm{C}$ is 10.83 , the ionisation constant of hydrofluoric acid in water at this temperature is:

$100 \mathrm{ml}$ solution (I) of buffer containing $0.1(\mathrm{M}) \mathrm{HA}$ and 0.2 (M) $\mathrm{A}^{-}$, is mixed with another solution (II) of $100 \mathrm{ml}$ containing 0.2(M) HA and 0.3(M) $\mathrm{A^{-}}$ .
After mixing what is the $\mathrm{pH}$ of resulting solution?
Given $\mathrm{pK}_{\mathrm{a}}$ of $\mathrm{HA}=5$

The change in $\mathrm{pH}$ of water when 0.01 mole of $\mathrm{NaOH}$ are added in 10 litre water is :

What minimum concentration of ${SO}_4^{2-}$ is required to precipitate ${BaSO}_4$ from the solution containing $1.0 \times 10^{-4}$ moles of ${Ba}^{2+}$ ? (Given $K_{S P}$ for ${BaSO}_4$ is $4 \times 10^{-10}$ )

${NH}_2-{COONH}_4({s}) \rightleftharpoons 2 {NH}_3({g})+{CO}_2({g})$. Total pressure at equilibrium is equal to $\left({K}_{{p}}=4 \mathrm{~atm}^3\right)$.

In which of the following solvents, will $\mathrm{AgBr}$ have highest solubility?

pH of aqueous NaCI solution after electrolysis

$10 \mathrm{~mL}$ of $10^{-4} \mathrm{NH}_2 \mathrm{SO}_4$ is diluted with water to have 1 $\mathrm{dm}^3$ solution : The $\mathrm{pH}$ of this solution is :

Statement I : The hydrolysis of an ester in acidic medium does not change with pressure.

Statement II : Pressure does not show effect on equilibrium reaction taking place in solution

STATEMENT I : $p H$ of aqueous solution of $\mathrm{NH}_4 \mathrm{Cl}$ is greater than 7.

STATEMENT II : Solution of a salt of weak base and strong acid is basic.

Given ${K}_{\mathrm{a}}$ values are $5.76 \times 10^{-10}$ and $4.8 \times 10^{-10}$ for ${NH}_4^{+}$and ${HCN}$ respectively. What is the equilibrium constant for the following reaction ?

${NH}_4^{+}(aq.) +{CN}^{-}(aq.) \rightleftharpoons {NH}_3 (aq.) +{HCN} (aq.)$

Equal volumes of two solutions of a strong acid having ${P^H} = 3\,and\,{P^H} = 4$ are mixed together. The ${P^H}$ of the resulting solution is $\left[ {\log 0.5 = - 0.3} \right]$

In which of the following case, the reaction will proceed in backward direction:

$\mathrm{H}_2(\mathrm{g})+\mathrm{I}_2(\mathrm{g}) \rightleftharpoons 2 \mathrm{HI}(\mathrm{g}), \mathrm{K_c}=0.25 \text { at } 298 \mathrm{~K}$

Which one is not correct statement about buffer mixture?

An acid base indicator which is a weak acid has a $\mathrm{p} K_{\mathrm{a}}$ value $=5.5$. At what concentration ratio of sodium acetate to acetic acid would the indicator show a colour half way between those of its acid and conjugate base forms? The $\mathrm{p} K_{\mathrm{a}}$ value of acetic acid $=4.75.$
$[\operatorname{Antilog}(0.75)=5.62, \text{Antilog}(0.79)= 6.3, \operatorname{Antilog}(0.69)=4.93].$

The vapour density of completely dissociated $\mathrm{N}{\mathrm{H}_4}\mathrm{Cl}$ would be:

Statement I : As per Lechutelier's principle, addition of heat to an equilibrium solid $\rightleftharpoons$ liquid results in decrease in the amount of solid.

Statement II : Reaction is endothermic, so on heating forward reaction is favoured.

Two buffers, $\mathrm{X}$ and $\mathrm{Y}$ of $\mathrm{pH}, 4.0$ and $6.0,$ respectively, are prepared from acid $\mathrm{HA}$ and the salt $\mathrm{NaA}.$ Both the buffers are $0.50 \mathrm{~M}$ in $\text{HA}.$ What would be the $\mathrm{pH}$ of the solution obtained by mixing equal volumes of the two buffers? The value of $K_{{a}}$ for $\mathrm{HA}=1.0 \times 10^{-5}(\log 5.05=0.7).$

A: Increasing the concentration of $\mathrm{H}_2$ will increase magnitude of equilibrium constant of the reaction $\mathrm{H}_2+\mathrm{I}_2 \rightleftharpoons 2 \mathrm{HI}$
R: Value of $\mathrm{K}_{\mathrm{C}}$ depends upon the concentration of reactants and products taken.