1. What is true about equilibrium state

a. forward reaction stops
b. reverse reaction stops
c. both forward and reverse reaction stops
d. both forward and reverse reaction continue at same rate

2. When a mixture of H2 and I2 is sealed in a flask and temperature is kept at 25oC , following equilibrium is established H2 + I2 <……> 2HI

Which substances or substances are present in the equilibrium mixture?

a. H2 and I2
b. HI only
c. I2 only
d. H2 I2 and HI

3. What are units for N2 + O2 <…….> 2NO2

a. mol/dm3
b. mol²/dm⁶
c. dm3/mol
d. no units

4 Which of following reaction will have no unit for Kc

a. H2 + CO2 <……..> H2O + CO
b. N2 + O2 <…….> 2NO2
c. 2A + B <……..> 3AC
d. all of these

5. Concentration of reactants and products at equilibrium remains unchanged if

a. conc of any reactant and product is not changed
b. temperature of the reaction is not changed
c. pressure and volume of the system is not changed
d. all of above are observed

6. Which of following doesnot happen when system is at equilibrium

a. forward and backward reaction stops
b. forward and backward reaction becomes equal
c. conc of reactants and products stops changing
d. reaction continue to occur in both directions.

7. In an irreversible reaction equilibrium is

a. established quickly
b. established slowly
c. never established
d. established when reaction stops

8. Active mass means

a. total mass of reactants
b. total mass of products
c. total mass of reactants and products
d. mass of substance in mol/dm3 in a dilute solution

9. For a reversible reaction Kc = [C]2/[A][B] Which substance is product of reaction?

a. A
b. B
c. both A and B
d. C

10. Which of the following factors does NOT affect the position of equilibrium?

a. Concentration of reactants
b. pressure
c. temperature
d. catalyst