A. In catalytic reactions, the catalyst reacts with the reactants
B. A catalyst initiates a chemical reaction
C. A catalyst lowers the activation energy of the reacting molecules
D. A catalyst cannot be recovered chemically unchanged at the end of the chemical reaction
Related Mcqs:
- Pick out the correct statement ?
A. A chemical reaction accompanied by absorption of heat is called an exothermic reaction
B. A chemical reaction accompanied by evolution of heat is called an endothermic reaction
C. The rate constant for a first order reaction does not change on changing the concentration units
D. Chemical equilibrium state is dynamic in nature - Pick out the correct statement ?
A. A catalyst speeds up the forward reaction but slows shown the reverse reaction
B. Addition of catalyst changes the equilibrium constant
C. Pressure changes do not change the equilibrium concentrations
D. The composition of equilibrium is changed by catalyst - Pick out the correct statement ?
A. A catalyst does not change AH of the reaction
B. A catalyst changes the equilibrium point
C. Law of mass action was suggested by Le-Chatelier
D. The difference between the energy of reactants and that of the products is the activation
energy - Pick out the correct statement?
A. A lower temperature favours the reaction of lower activation energy
B. The dispersion number for a reactor/vessel is uL/D
C. The rate controlling step in a reaction involving many steps is the fastest step
D. Pore volume and porosity of a catalyst is measured by Brunauer-Emmett-Teller (BET)
technique - Pick out the correct statement?
A. Reactions with high activation energies are very temperature sensitive
B. Chemical equilibrium is a static state
C. A photochemical reaction is catalysed by light
D. A chemical reaction occurs when the energy of the reacting molecule is less than the activation energy of the reaction - If n = overall order of a chemical reaction. a = initial concentration of reactant. t = time required to complete a definite fraction of the reaction. Then pick out the correct relationship ?
A. t ∝ 1/an
B. t ∝ 1/an – 1
C. t ∝ 1/an + 1
D. t ∝ an - Pick out the wrong statement ?
A. For a first order consecutive reaction, a tubular flow reactor as compared to a stirred tank
reactor provides higher overall selectivity
B. For an ideal mixed reactor at steady state, the exit stream has the same composition as fluid
within the reactor and the space time is equivalent to holding time for constant density system
C. Plug flow reactor (PFR) is always smaller than mixed reactor for all positive reaction orders
for a particular duty
D. Reaction rate does not decrease appreciably as the reaction proceeds in case of an
autocatalytic reaction - Pick out the wrong statement ?
A. A catalyst does not alter the final position of equilibrium in a reversible reaction
B. A catalyst initiates a reaction
C. A catalyst is specific in reaction
D. A catalyst remains unchanged in chemical composition at the end the reaction - Pick out the wrong statement?
A. Catalytic activity of enzyme catalysed reactions which is affected by temperature, pH value &
chemical agents, is maximum at a temperature of about 45°C
B. Most of the enzyme catalysed reactions involve at least two substrates
C. Enzymes help in increasing the activation energy of the reaction
D. Equilibrium concentrations in enzyme catalysed reactions can be calculated by using the
thermodynamic properties of substrates & products - Pick out the wrong statement?
A. Use of different catalysts in a reversible catalytic chemical reaction does not change the
equilibrium composition
B. Alumina is added as a promoter to iron catalyst in ammonia synthesis reaction
C. Activation energy for a reaction is obtained from the intercept of the Arrhenius plot
D. Presence of inerts affects the equilibrium conversion of
