Application of Equilibrium Constant

IMPORTANT

Application of Equilibrium Constant: Overview

This topic covers concepts such as Degree of Dissociation for Equilibrium Reactions, Calculating Reaction Quotient, Applications of Equilibrium Constants, Predicting Direction of Reaction, Predicting Extent of Reaction, etc.

Important Questions on Application of Equilibrium Constant

EASY
IMPORTANT

When two reactants, A and B are mixed to give products C and D, the reaction quotient Q, at the initial stage of the reaction :–

EASY
IMPORTANT

When two reactants A and B are mixed to give products C and D, the reaction quotient Q at the initial stage of the reaction is best described by-

MEDIUM
IMPORTANT

Phosphorus pentachloride dissociates as follows, in a closed reaction vessel,   PCl 5 (g)   PCl 3 (g) + Cl 2 (g)

If total pressure at equilibrium of the reaction mixture is P and degree of dissociation of   PCl 5 is x, the partial pressure of   PCl 3 will be :

MEDIUM
IMPORTANT

COCl2 gas dissociates according to the equation, COCl2COg+Cl2g. When heated to 700 K the density of the gas mixture at 1.16 atm and at equilibrium is 1.16 g/litre. The degree of dissociation of CO2 at 700 K is

MEDIUM
IMPORTANT

When the reaction A+2B2C+D was studied, it was observed that the initial concentration of B was 1.5 times that of A, and the equilibrium concentrations of A and C were equal. Then Kc for the given equilibrium equals

MEDIUM
IMPORTANT

Identify the correct expression for the equilibrium constant of the following reaction:
2X(g)+Y(g)3Z(g)

EASY
IMPORTANT

Predict the extent of a reaction, N2g+O2g2NOg at 298 K has Kc=4.8×10-31.

EASY
IMPORTANT

N2O4g2NO2g; Kc=5.7×10-9 at 298 K. At equilibrium

EASY
IMPORTANT

If Kc is very large 

EASY
IMPORTANT

Explain the classification of chemical equilibrium based on the extent of completion.

MEDIUM
IMPORTANT

A sample of pure PCl5 was introduced into an evacuated vessel at 473 K. After equilibrium was attained, the concentration of PCl5 was found to be 0.05 mol L-1. If the value of Kc is 8.3×10-3, what is the concentrations of Cl2 at equilibrium?

PCl5gPCl3g+Cl2g

EASY
IMPORTANT

The equilibrium:

NH4HSsNH3g+H2Sg

is allowed  to set-up at 127°C in a closed vessel. The total pressure at equilibrium was 20 atm. The Kc for the reaction is

HARD
IMPORTANT

In an aqueous solution of volume 500 mL, when the reaction of 2Ag++CuCu2++2Ag is reached equilibrium the Cu2+, was x M. When 500 mL of water is further added, at the equilibrium Cu2+ will be

MEDIUM
IMPORTANT

The degree of dissociation is 0.4 at 420 K and 1.0 atm for the gaseous reaction

PCl5gPCl3g+Cl2(g)

Assuming ideal behaviour of all gases, calculate the density of equilibrium mixture of equilibrium mixture at 420 K and 1.0 atm. (P = 31, Cl = 35.5)

HARD
IMPORTANT

40% of a mixture of 2 moles of N2 and 6 moles of H2 react to give NH3 according to the equation N2 g+3H2 g2NH3 g at constant temperature and pressure. Then the ratio of the final volume to the initial volume of gases are

MEDIUM
IMPORTANT

The degree of dissociation of acetic acid in a 0.1 N solution is 1.32×10-2. At what concentration of nitrous acid will its degree of dissociation be the same as that of acetic acid?

Ka for HNO2 = 4 × 10-4

(Report your answer by multiplying the value with 10)

MEDIUM
IMPORTANT

At what concentration of the solution will the degree of dissociation of nitrous acid be 0.2?

 (Ka for HNO2 is 4×10-4)

Report the value by multiplying with 1000 and rounding off to one significant figure.

HARD
IMPORTANT

5 moles of SO2 and 5 moles of O2 react in a closed vessel. At equilibrium 60% of the SO2 is consumed. The total number of gaseous moles (SO2, O2 and SO3) in the vessel is:

MEDIUM
IMPORTANT

0.6 mole of PCl5, 0.3 mole of PCl3 and 0.5 mole of Cl2 are taken in a 1L flask to obtain the following equilibrium:
PCl5(g)PCl3(g)+Cl2(g)
If the equilibrium constant Kc for the reaction is 0.2. Predict the direction of the reaction.

HARD
IMPORTANT

Explain the classification of chemical equilibrium on the basis of extent of completion.