CHEMICAL KINETICS EAMCET MCQ’S
1. The role of a catalyst
is to change ______________.
(i)
gibbs energy of reaction.
(ii)
enthalpy of reaction.
(iii)
activation energy of reaction.
(iv)
equilibrium constant.
2. In the presence of a catalyst,
the heat evolved or absorbed during the reaction
___________.
(i)
increases.
(ii)
decreases.
(iii)
remains unchanged.
(iv)
may increase or decrease.
3. Activation energy of a
chemical reaction can be determined by _____________.
(i)
determining the rate constant at standard temperature.
(ii)
determining the rate constants at two
temperatures.
(iii)
determining probability of collision.
(iv)
using catalyst.
4. Consider the Arrhenius equation given below and mark the correct
option.
–Ea/RT
k = A e
(i)
Rate constant increases exponentially with increasing activation energy
and
decreasing temperature.
(ii)
Rate constant decreases exponentially with increasing activation energy
and
decreasing temperature.
(iii)
Rate constant increases exponentially with decreasing activation energy
and
decreasing temperature.
(iv)
Rate constant increases exponentially with decreasing activation energy
and
increasing temperature.
5. Which of the following statements is not correct about
order of a reaction.
(i)
The order of a reaction can be a fractional number.
(ii)
Order of a reaction is experimentally determined quantity.
(iii)
The order of a reaction is always equal to the sum of the stoichiometric
coefficients
of reactants in the balanced chemical equation for a reaction.
(iv)
The order of a reaction is the sum of the powers of molar concentration
of
the reactants in the rate law expression
6. Which of the following
statements is correct?
(i)
The rate of a reaction decreases with passage of time as the concentration
of
reactants dereases.
(ii)
The rate of a reaction is same at any time during the reaction.
(iii)
The rate of a reaction is independent of temperature change.
(iv)
The rate of a reaction decreases with increase in concentration of
reactant(s)
7. Which of the following
statements is incorrect about the collison theory of
chemical
reaction?
(i)
It considers reacting molecules or atoms to be hard spheres and ignores
their
structural features.
(ii)
Number of effective collisions determines the rate of reaction.
(iii)
Collision of atoms or molecules possessing sufficient threshold energy
results
into the product formation.
(iv)
Molecules should collide with sufficient threshold energy and proper
orientation
for the collision to be effective
8. Which of the following
statement is not correct for the catalyst?
(i)
It catalyses the forward and backward reaction to the same extent.
(ii)
It alters ΔG of the reaction.
(iii)
It is a substance that does not change the equilibrium constant of a
reaction.
(iv)
It provides an alternate mechanism by reducing activation energy
between
reactants and products.
9. The value of rate
constant of a pseudo first order reaction ____________.
(i)
depends on the concentration of reactants present in small amount.
(ii)
depends on the concentration of reactants present in excess.
(iii)
is independent of the concentration of reactants.
(iv)
depends only on temperature
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