Rate Law
CSIR NET & GATE MCQs
Chemical Kinetics
Topic wise Assignment-1
Q1. For the reaction 2A + B → C
+ 2D, which is first order in A and also first order in B, the rate is given by
(a) k[A]2[B]
(b) k[A][B]2
(c) k[A]2
(d) k[A][B]
Q2. If r = [A]o2 [B]o2
for a reaction, by what factor is the initial rate multiplied if the [A]o
is multiplied by 1.5 and the [B]o is multiplied by 3.0?
(a) 4.5
(b) 2.25
(c) 6.75
(d) 1.21
Q3. If rate expression for the reaction
A(g) + B(g) → C(g) is, rate = k [A]1/2 [B]2.
What changes in rate if initial concentration of A and B increase by factor 4
and 2 respectively?
(a) 4
(b) 6
(c) 8
(d) 12
Q4. For an ideal gas’s reaction, the rate
is generally expressed in terms of dP/dt instead of dC/dt or dn/dt (where C=n/V
is the concentration and n is number of moles). What is the relation among
these three expressions if T and V are constants?
Q5. Reaction A →
B follows second order kinetics. Doubling the concentration of A will increase
the rate of formation of B by a factor of
(a) 1/4
(b) 1/2
(c) 2
(d) 4
Q6. An elementary reaction between A and
B is a second order reaction. Which of the following rate equations must be
correct?
(a) r = k [A]2 [B]0
(b) r = k [A]3/2 [B]1/2
(c) r = k [A]0 [B]2
(d) r = k [A] [B]
Q7. The unit of rate of reaction and
constant are the same for
(a) zero order reaction
(b) first order reaction
(c) second order reaction
(d) third order reaction
Q8. If the rates of reaction are R1
and R2 at concentrations C1 and C2 of a
reactant respectively, the order of reaction n (assuming that the
concentrations of all other reactants and T remains constant) with respect to
that of reactant is given by
[NET June 2016]
Q9. For an elementary reaction 2A + B → A2B, if the volume of vessel is quickly
reduced to half of its original volume then rate of reaction will __________.
(a) remain unchanged
(b) increase four times
(c) increase eight times
(d) decrease eight times
Ans Key
Q1.d Q2.c Q3.c Q4.b Q5.d Q6.d Q7.a Q8.a Q9.c