Practice Test: Question Set - 32
1. In a reversible chemical reaction having two reactants in equilibrium, if the concentration of the reactants are doubled, then the equilibrium constant will
- (A) Remain the same
- (B) Be halved
- (C) Also be doubled
- (D) Become one fourth
2. Which of the following is an autocatalytic reaction?
- (A) Photochemical reactions
- (B) Microbial fermentation reaction
- (C) Enzyme fermentation reaction
- (D) Ammonia synthesis reaction
3. When a catalyst increases the rate of forward reaction, the value of rate constant
- (A) Increases
- (B) Decreases
- (C) Remain same
- (D) Becomes infinite
4. What is the unit of the rate constant in a chemical reaction in which 10% of the reactant decomposes in one hour, 20% in two hours, 30% in three hours and so on?
- (A) Liter/mole.second
- (B) Moles/liter.second
- (C) Liter/mole
- (D) Liter/second
5. Catalyst carriers
- (A) Have very high selectivity
- (B) Increase the activity of a catalyst
- (C) Provide large surface area with a small amount of active material
- (D) Inhibit catalyst poisoning
6. With increase in temperature, the equilibrium __________ rises in case of endothermic reaction.
- (A) Constant
- (B) Conversion
- (C) Both (a) & (b)
- (D) Neither (a) nor (b)
7. Rate determining step in a reaction consisting of a number of steps in series is the __________ step.
- (A) Fastest
- (B) Slowest
- (C) Intermediate
- (D) Data insufficient; can't be predicted
8. Reverse reaction in a chemical equilibrium is favored by the
- (A) Removal of one of the products regularly
- (B) Increase in the concentration of one of the products
- (C) Increase in the concentration of one of the reactants
- (D) None of these
9. __________ is the controlling step in a highly temperature sensitive fluid-solid non-catalytic reaction.
- (A) Gas film diffusion
- (B) Ash diffusion
- (C) Chemical reaction
- (D) None of these
10. When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value.
- (A) Twice
- (B) Half
- (C) Equal
- (D) None of these
11. What is the Thiele modulus of the solid catalyzed first order reaction as shown in the bellow figure, if the pore diffusion offers negligible resistance to reaction?
- (A) < 5
- (B) < 0.5
- (C) > 1
- (D) 5
12. For a first order chemical reaction, the rate constant
- (A) Changes on changing the concentration units
- (B) Is not a function of the unit of time
- (C) Has unit of time-1
- (D) None of these
13. If in the gaseous phase reaction, N2O4 ⇌ 2NO2, x is the part of N2O4 which dissociates, then the number of molecules at equilibrium will be
- (A) (1 + x)
- (B) (1 - x)
- (C) (1 + x)2
- (D) (1 - x)2
14. For a fluidized bed reactor, the most suitable/relevant model is a __________ model.
- (A) Tank in series
- (B) Bubbling bed
- (C) Plug flow
- (D) None of these
15. The catalyst in a second order reversible reaction increases the rate of the forward reaction
- (A) And decreases that of backward reaction
- (B) And backward reaction equally
- (C) Only
- (D) To a greater extent than that of the backward reaction