JEE Equilibrium PYQs with Solutions PDF, Check and Download

The first and second ionization constants of $$H_{2}X$$ are $$2.5 \times 10^{-8}$$ and $$1.0 \times 10^{-13}$$ respectively. The concentration of $$X^{2-}$$ in $$0.1 MH_{2} X$$ solution is _________ $$\times 10^{-15}M$$. (Nearest Integer)

Which of the followmg mixture gives a buffer solution with pH=9.25?
Given : $$pK_{b}$$ $$(NH_{4}OH)$$ = 4.75

For the following gas phase equilibrium reaction at constant temperature,
$$NH_{3}(g)\rightleftharpoons 1/2N_{2}(g)+3/2H_{2}(g)$$
if the to tal pressure is $$\sqrt{3}$$ atm and the pressure equilibrium constant ($$K_{p}$$) is 9 atm, then the degree of dissociation is given as $$(x\times 10^{-2})^{-1/2}$$.The value of x is ______. (nearest integer)

Dissociation of a gas $$A_{2}$$ takes place according to the following chemical reaction.
At equilibrium, the total pressure is 1 bar at 300K.

$$A_{2}(g)\rightleftharpoons 2A(g)$$

The standard Gibbs energy of formation of the involved substances has been
provided below:

The degree of dissociation of $$A_{2} (g)$$ is given by $$(x\times10^{-2})^{1/2} $$ where $$x$$ =
_____ . (Nearest integer).
[Given: $$R=8 J \text{ }mol^{-1}K^{-1},\log{2}=0.3010, \log {3}=0.48]$$
Assume degree of dissociation is not negligible.

Consider two Group IV metal ious $$X^{2+}\text{ and }Y^{2+}$$
A solution containing $$0.01 M X^{2+}\text{ and }0.01MY^{2+}$$ is satmated with $$H_{2}S$$. The pH at which the metal sulphide YS will form as a precipitate is __ . (Nearest integer)
$$(Given:K_{sp}(XS)=1\times 10^{-22} \text{ at } 25^{\circ}C,K_{sp}(YS)=4\times 10^{-16} \text{ at } 25^{\circ}C,[H_{2}S]=0.1M\text{ in solution },K_{a1}\times K_{a2}(H_{2}S)=1.0\times 10^{-21},\log{2}=0.30,\log{3}=0.48,\log{5}=0.70)$$

Consider the following gaseous equilibrimn in a closed container of volume 'V' at T(K).
$$P_{2}(g)+Q_{2}(g)\rightleftharpoons 2PQ(g)$$
2 moles each of $$P_{2}(g)$$, $$Q_{2}(g)$$ and PQ(g) are present at equilibrium. Now one mole each of'$$P_{2}$$' and '$$Q_{2}$$' are added to the equilibrium keeping the temperature at T(K). The number of moles of $$P_{2}$$, $$Q_{2}$$ and PQ at the new equilibrium, respectively, are

Molar conductivity of a weak acid HQ of concentration 0.18 M was found to be 1/30 of the molar conductivity of another weak acid HZ with concentration of 0.02M. If $$\lambda^{\circ}{}_{Q}-$$ happened to be equal with $$\lambda^{\circ}{}_{Z}-$$, then the difference of the $$pK_{a}$$ values of the two weak acids $$(pK_{a}(HQ) - pK_{a}(HZ))$$ is ___ (Nearest integer).
[Given: degree of dissociation ($$\alpha$$) << 1 for both weak acids, $$\lambda^{\circ}$$ : limiting molar conductivity of ions]

Consider a weak base 'B' of $$pK_{b}=5.699 $$. 'x' mL of 0.02 M HCI and 'y' mL of 0.02 M weak base 'B' are mixed to make 100 mL of a buffer of pH 9 at 25 °C. The values of 'x' and 'y' respectively are:
[Given: log 2 = 0.3010, log 3 = 0.4771, log 5 = 0.699]

Consider the dissociation equilibrium of the following weak acid $$HA\rightleftharpoons H^{+}(aq)+A^{-}(aq)$$If the pKa of the acid is 4, then the pH of 10 mM HA solution is __ .(Nearest integer)
[Given: The degree of dissociation can be neglected with respect to unity]

$$X_2(g ) + Y_2(g ) \rightleftharpoons 2Z(g)$$

$$X_2(g )$$ and $$Y_2(g )$$ are added to a 1 L flask and it is found that the system attains the above equilibrium at T(K) with the number of moles of $$X_2(g ),\text{ } Y_2(g )$$ and $$Z(g)$$ being 3, 3 and 9 mol respectively (equilibrium moles). Under this condition of equilibrium, 10 mol of $$Z(g$$) is added to the flask and the temperature is maintained at $$T(K)$$. Then the number of moles of $$Z(g)$$ in the flask when the new equilibrium is established is __ . (Nearest integer)

Observe the following equilibrium in a 1 L flask.
$$A(g)\rightleftharpoons B(g)$$
At T(K), the equilibrium concentrations of A and B are 0.5 Mand 0.375 M respectively. 0.1 moles of A is added into the flask and heated to T(K) to establish the equilibrium again. The new equilibrium concentrations (in M) of A and B are respectively

The molar solubility(s) of zirconium phosphate with molecular formula $$(Zr^{4+})_{3}(PO_{4}^{3-})_{4}$$ is given by relation :

A vessel at 1000 K contains $$CO_2$$ with a pressure of 0.5 atm . Some of $$CO_2$$ is converted into CO on addition of graphite. If total pressure at equilibrium is 0.8 atm , then Kp is :

Consider the reaction $$X_{2}Y(g)=X_{2}(g)+\frac{1}{2}Y_{2}(g)$$ The equation representing correct relationship between the degree of dissociation (x) of $$X_{2}Y(g)$$ with its equilibrium constant Kp is ______ . Assume x to be very very small.

pH of water is 7 at $$25^{\circ}C$$.If water is heated to $$80^{\circ}C$$.,it's pH will :

$$ 37.8\,g\,N_2O_5$$ was taken in a  $$1\,L$$ reaction vessel and allowed to undergo the following reaction at 500 K  $$2N_2O_5(g) \rightleftharpoons 2N_2O_4(g) + O_2(g)$$ The total pressure at equilibrium was found to be  $$18.65\,$$bar.  Then, $$K_p = \underline{\hspace{2cm}}\times10^{-2}$$  [nearest integer]. Assume  $$N_2O_5$$  to behave ideally under these conditions. Given:  $$R=0.082\,bar\,L\,mol^{-1}K^{-1}$$

$$\text{For the reaction, } H_2(g) + I_2(g) \rightleftharpoons 2HI(g),$$  Attainment of equilibrium is predicted correctly by:

A weak acid HA has degree of dissociation x . Which option gives the correct expression of $$(pH pK_{a})$$ ?

At temperature $$T$$, compound $$AB_{2(g)}$$ dissociates as $$AB_{2} \rightleftharpoons AB_{(g)}+\frac{1}{2}B_{2(g)}$$ having degree of dissociation $$x$$ (small compared to unity). The correct expression for $$x$$ in terms of $$K_{p}$$ and p is

Which of the following happens when $$NH_{4}OH$$ is added gradually to the solution containing 1 M $$A^{2+}$$ and $$1MB^{3+}$$ ions? Given : $$K_{sp}[A(OH)_{2}]= 9 \times 10^{-10}$$ and $$K_{sp}[B(OH)_{3}]= 27 \times 10^{-18}$$ at 298 K .

If 1 mM solution of ethylamine produces pH=9, then the ionization constant $$(K_{b})$$ of ethylamine is $$10^{-x}$$. The value of is ______ (nearest integer). [The degree of ionization of ethylamine can be neglected with respect to unity.]

Consider the equilibrium $$CO(g)+3H_{2}(g)\rightleftharpoons CH_{4}(g)+H_{2}O(g)$$ If the pressure applied over the system
increases by two fold at constant temperature then (A) Concentration of reactants and products increases. (B) Equilibrium will shift in forward direction. (C) Equilibrium constant increases since concentration of products increases. (D) Equilibrium constant remains unchanged as concentration of reactants and products remain same. Choose the correct answer from the options given below :

What will be the decreasing order of basic strength of the following conjugate bases? $$^-OH,\ R\bar{O},\ CH_3CO\bar{O},\ C\bar{l}$$

In the precipitation of the iron group (III) in qualitative analysis, ammonium chloride is added before adding ammonium hydroxide to:

Arrange the following in increasing order of solubility product :$$\mathrm{Ca(OH)_2, \ AgBr, \ PbS, \ HgS}$$

$$K_a$$ for $$CH_3COOH$$ is $$1.8 \times 10^{-5}$$ and $$K_b$$ for $$NH_4OH$$ is $$1.8 \times 10^{-5}$$. The pH of ammonium acetate solution will be:

Solubility of calcium phosphate (molecular mass, M) in water is W g per 100 mL at 25°C. Its solubility product at 25°C will be approximately.

Which of the following is strongest Bronsted base?

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 :

For the reaction $$N_2O_4(g) \rightleftharpoons 2NO_2(g)$$, $$K_p = 0.492$$ atm at $$300$$ K. $$K_c$$ for the reaction at same temperature is _______ $$\times 10^{-2}$$. (Given: $$R = 0.082$$ L atm mol$$^{-1}$$ K$$^{-1}$$)

The following concentrations were observed at $$500$$ K for the formation of $$NH_3$$ from $$N_2$$ and $$H_2$$. At equilibrium: $$[N_2] = 2 \times 10^{-2}$$ M, $$[H_2] = 3 \times 10^{-2}$$ M and $$[NH_3] = 1.5 \times 10^{-2}$$ M. Equilibrium constant for the reaction is ______.

The pH at which $$Mg(OH)_2 [K_{sp} = 1 \times 10^{-11}]$$ begins to precipitate from a solution containing $$0.10 \text{ M } Mg^{2+}$$ ions is ______.

The pH of an aqueous solution containing 1M benzoic acid ($$pK_a = 4.20$$) and 1M sodium benzoate is 4.5. The volume of benzoic acid solution in 300 mL of this buffer solution is _________ mL.

For the given reaction, choose the correct expression of $$K_C$$ from the following: $$\text{Fe}^{3+}_{(aq)} + \text{SCN}^-_{(aq)} \rightleftharpoons (\text{FeSCN})^{2+}_{(aq)}$$

$$A_g \rightleftharpoons B_g + \frac{C}{2}_g$$. The correct relationship between $$K_P$$, $$\alpha$$ and equilibrium pressure $$P$$ is

The equilibrium constant for the reaction $$SO_3(g) \rightleftharpoons SO_2(g) + \frac{1}{2}O_2(g)$$ is $$K_c = 4.9 \times 10^{-2}$$. The value of $$K_c$$ for the reaction given below is $$2SO_2(g) + O_2(g) \rightleftharpoons 2SO_3(g)$$:

Given below are two statements : Statement I : On passing $$HCl_{(g)}$$ through a saturated solution of $$BaCl_2$$, at room temperature white turbidity appears. Statement II : When HCl gas is passed through a saturated solution of NaCl, sodium chloride is precipitated due to common ion effect. In the light of the above statements, choose the most appropriate answer from the options given below :

Consider the given chemical reaction sequence :

Total sum of oxygen atoms in Product A and Product B are ______

Consider the given reaction, identify the major product "P". $$CH_3 - COOH \xrightarrow{(i) LiAlH_4 \; (ii) PCC \; (iii) HCN/OH^{-} \; (iv) H_2O/OH^{-}, \Delta}$$ "P"

The correct sequence of acidic strength of the following aliphatic acids in their decreasing order is: $$CH_3CH_2COOH, CH_3COOH, CH_3CH_2CH_2COOH, HCOOH$$