Chemical Equilibrium Questions

If the pressure in a reaction vessel for the following reaction is increased by decreasing the volume, what will happen to the concentrations of CO and CO₂ ? H₂O(g) + CO(g) ⇌ H₂(g) + CO₂(g) + Heat

Consider the following reactions at equilibrium and determine which of the indicated changes will cause the reaction to proceed to the right - (1) CO(g) + 3H₂(g) ⇌ CH₄(g) + H₂O(g) (add CH₄) (2) N₂(g) + 3H₂(g) ⇌ 2NH₃(g) (remove NH₃) (3) H₂(g) + F₂(g)

Some inert gas is added at constant volume to the following reaction at equilibrium NH₄HS(s) ⇌ NH₃(g) + H₂S(g) Predict the effect of adding the inert gas -

Given the following reaction at equilibrium, N₂(g) + 3H₂(g) ⇌ 2NH₃(g) Some inert gas at constant pressure is added to the system. Predict which of the following facts will be affected ?

Determine the value of equilibrium constant (Kc) for the reaction A₂(g) + B₂(g) ⇌ 2AB(g) If 10 moles of A₂, 15 moles of B₂ and 5 moles of AB are placed in a 2 litre vessel and allowed to come to equilibrium. The final concentration of AB is 7.5 M :

The figure shows the change in concentration of species A and B as a function of time. The equilibrium constant Kc for the reaction A(g) ⇌ 2B(g) is -

Percentage yield of following reaction is plotted against pressure at a definite temperature : 2SO₂(g) + O₂(g) ⇌ 2SO₃(g); ΔH = −ve Which of the following relation is correct ?

Decomposition of N₂O₄(g) takes place as follows : N₂O₄(g) ⇌ 2NO₂(g) 'D' is the vapour density at initial stage and 'd' is the vapour density at equilibrium. We get following graph when the degree of dissociation 'a' is plotted against (D/d) What is t

For the reaction, PCl₅(g) ⇌ PCl₃(g) + Cl₂(g), the forward reaction at constant temperature is favoured by - I. introducing inert gas at constant volume. II. introducing inert gas at constant pressure. III. decreasing pressure of the reaction mixture.

At 35°C, the equilibrium constant for the reaction below is 2NOCl(g) ⇌ 2NO(g) + Cl₂(g) Kc = 1.6 × 10⁻⁵ An equilibrium mixture was found to have the following concentration of Cl₂ and NOCl. [Cl₂] = 1.2 × 10⁻² M [NOCl] = 2.8 × 10⁻¹ M Calculate the conc

In the reaction : NH₂COONH₄(s) ⇌ 2NH₃(g) + CO₂(g) the equilibrium pressure was 3 atm at 1000 K. The Kp of the reaction -

At constant pressure, the presence of inert gases -

Consider the reaction, (i) PCl₅(g) ⇌ PCl₃(g) + Cl₂(g) (ii) N₂O₄(g) ⇌ 2NO₂(g) The addition of an inert gas at constant volume -

For the reaction, N₂O₄(g) ⇌ 2NO₂(g); if percentage dissociation of N₂O₄ are 25%, 50%, 75% and 100%, then the sequence of observed vapour densities will be -

On heating a mixture of SO₂Cl₂ and CO, two equilibria are simultaneously established : SO₂Cl₂(g) ⇌ SO₂(g) + Cl₂(g) CO(g) + Cl₂(g) ⇌ COCl₂(g) On adding more SO₂ at equilibrium what will happen ?

Which of the following is not favourable for formation of SO₃ ? 2SO₂(g) + O₂(g) ⇌ 2SO₃(g); ΔH = −188 KJ

The reaction A + B ⇌ C + D is studied in a one litre vessel at 250°C. The initial concentration of A was 3n and the initial concentration of B was n. After equilibrium was attained then equilibrium concentration of C was found to be equal to equilibr

2.0 mol of PCl₅ were introduced in a vessel of 5.0 L capacity at a particular temperature. At equilibrium, PCl₅ was found to be 35% dissociated into PCl₃ and Cl₂. The value of Kc for the reaction is -

At 35°C, the equilibrium constant for the reaction below is 2NOCl(g) ⇌ 2NO(g) + Cl₂(g) Kc = 1.6 × 10⁻⁵ An equilibrium mixture was found to have the following concentration of Cl₂ and NOCl. [Cl₂] = 1.2 × 10⁻² M [NOCl] = 2.8 × 10⁻¹ M Calculate the conc

For NH₄HS(s) ⇌ NH₃(g) + H₂S(g), if Kp = 64 atm², equilibrium pressure of mixture is :

The endothermic reaction MCO₃(s) ⇌ MO(s) + CO₂(g) is taking place in such a way that the vapour pressure of CO₂ is equal to atmospheric pressure. Which of the following is not correct ?

CaCO₃(s) ⇌ CaO(s) + CO₂(g) For above reaction, ΔG° (standard Gibb's free energy) will be :

In a dilute solution there are two equilibria KCl(s) ⇌ K⁺ + Cl⁻ ... K₁ = 10ˣ Ag⁺ + Cl⁻ ⇌ AgCl(s) ... K₂ = 10ʸ The equilibrium constant for the reaction Ag⁺ + KCl(s) ⇌ K⁺ + AgCl(s) in dilute solution is -

When 1 mole H₂O(g) and 1 mole CO(g) are heated at 1000°C in a closed vessel of 5 litre, it was found that 40% of H₂O react at equilibrium, according to H₂O(g) + CO(g) ⇌ H₂(g) + CO₂(g) Kc of the reaction will be -

For the reaction : 2HI(g) ⇌ H₂(g) + I₂(g); the degree of dissociation (α) of HI(g) is related to equilibrium constant Kp by the expression

A(l) + B(l) ⇌ C(l) + D(l) One mole of A and one mole of B are mixed in a volume of one litre. If 0.9 mole per litre of C is found at equilibrium, the equilibrium constant Kc is –

In Bodenstein experiment, one mol H₂ and two mol I₂ are taken initially in a one litre flask. If at equilibrium 0.5 mol H₂ are present, the equilibrium concentrations of I₂ and HI in mol l⁻¹ are –

Which of the following conditions will be favourable for the formation of HX according to the gaseous equilibrium : H₂X₂ + heat ⇌ 2HX –

If K₁ = 4 × 10⁻³ for first gaseous reaction – SO₂(g) + 1/2 O₂(g) ⇌ SO₃(g); K₁ 2SO₃(g) ⇌ 2SO₂(g) + O₂(g); K₂ then K₂ will be –

At a total equilibrium pressure of 1.0 atmosphere, the degree of dissociation of phosgene is 0.2 COCl₂(g) ⇌ CO(g) + Cl₂(g) Now the same equilibrium is established at the same temperature in presence of N₂ gas at a partial pressure of 0.4 atm. in a to

The oxidation of SO₂ to SO₃ by oxygen is an exothermic reaction. The yield of SO₃ will be maximum if –

When 120 g acetic acid is reacted with 138 g ethyl alcohol, the amount of alcohol consumed is 30% of its initial concentration. The number of moles of acetic acid at equilibrium are –

In the formation of nitric acid, N₂ and O₂ are made to combine. Thus N₂ + O₂ ⇌ 2NO − Heat Which of the following conditions will favour the formation of NO –

At 500K, the equilibrium constant for the reaction cis-C₂H₂Cl₂ ⇌ trans-C₂H₂Cl₂ is 0.6. At the same temperature, the equilibrium constant for the reaction trans-C₂H₂Cl₂ ⇌ cis-C₂H₂Cl₂ will be –

In the equilibrium N₂ + 3H₂ ⇌ 2NH₃ + 22 Kcal the formation of ammonia is favoured by –

In an equilibrium reaction for which ΔG° = 0, the equilibrium constant K should be equal to –

In the study of the reaction – Cl₂ + PCl₃ ⇌ PCl₅ partial pressures of Cl₂, PCl₃ and PCl₅ at equilibrium are 0.1, 0.1 and 0.2 atm respectively at 250° C. At the same temperature, in another experiment on the same reaction, at equilibrium the partial p

The reaction in which the yield of the products cannot be increased by the application of high pressure is –

For the reaction at equilibrium – CO₂(g) + H₂(g) ⇌ CO(g) + H₂O(g) [P – total pressure and x = degree of dissociation]

2SO₂ + O₂ ⇌ 2SO₃ + 47 Kcal. If large excess of oxygen is added to the above system in equilibrium this will -

At 250° C, the vapour density of PCl₅ is Y (at equilibrium) and molar mass is Q (Initially). Its degree of dissociation is then equal to -

The equilibrium constant for the reaction N₂(g) + O₂(g) ⇌ 2NO(g) is 4 × 10⁻⁴ at 2000 K. In the presence of catalyst, the equilibrium is attained 10 times faster. The equilibrium constant in the presence of catalyst, at 2000 K is–

If Kp for the reaction A(g) + 2B(g) ⇌ 3C(g) + D(g) is 0.05 atm. at 1000 K. Its Kc in terms of R will be –

At a given temperature the following reaction is allowed to reach equilibrium in a vessel of volume V₁ litre. The degree of dissociation is α₁. If by keeping the temperature fixed the volume of the reaction vessel is doubled (assuming the degrees of

An equilibrium mixture for the reaction 2H₂S(g) ⇌ 2H₂(g) + S₂(g) had 1 mole of H₂S, 0.2 mole of H₂ and 0.8 mole of S₂ in a 2 litre flask. The value of Kc in mol lit.⁻¹ is–

The value of Kp for the reaction 2H₂S(g) ⇌ 2H₂(g) + S₂(g) is 1.2 × 10⁻² at 1065°C. The value of Kc for this reaction is–

For dissociation of PCl₅,mole fraction of Cl₂ at equilibrium is 0.3. The total pressure is 1.0 atmosphere. The partial pressure of PCl₃ at equilibrium is –

When the equilibrium : 2NH₃ ⇌ N₂ + 3H₂ has been established, NH₃ is found to be 20% dissociated. The ratio of total number of moles at equilibrium to the moles of NH₃ at equilibrium is –

The ratio of Kp / Kc for the reaction : CO(g) + 1/2 O₂(g) ⇌ CO₂(g) is –

In A + B + Heat ⇌ C, then reaction is favoured at –