NCERT MCQ CLASS-12 CHAPTER-4 | CHEMISTRY NCERT MCQ | CHEMICAL KINETICS | EDUGROWN

In This Post we are  providing Chapter-4 Chemical Kinetics NCERT MCQ for Class 12 Chemistry which will be beneficial for students. These solutions are updated according to 2021-22 syllabus. These MCQS  can be really helpful in the preparation of Board exams and will provide you with a brief knowledge of the chapter.

NCERT MCQ ON CHEMISTRY KINECTICS

Question 1.
A first order reaction has a half life period of 34.65 seconds. Its rate constant is
(a) 2 × 10^-2 s^-1
(b) 4 × 10^-4 s^-1
(c) 20 s^-1
(d) 2 × 10^-4 s^-1

Answer: (a) 2 × 10^-2 s^-1

Question 2.
If a graph is plotted between In k and 1/T for the first order reaction, the slope of the straight line so obtained is given by
(a) –EaR
(b) Ea2.303R
(c) 2.303Ea.R
(d) Ea2.303

Answer: (a) –EaR

Question 3.
The unit of rate constant for a zero order reaction is
(a) mol L^-1s^-1
(b) s^-1
(c) L mol^-1s^-1
(d) L²mol^-2s^-1

Answer: (a) mol L^-1s^-1

Question 4.
A catalyst increases the speed of a chemical reaction by
(a) increasing activation energy
(b) decreasing activation energy
(c) increasing reactant energy
(d) decreasing threshold energy

Answer: (b) decreasing activation energy

Question 5.
The units of the rate constant for the second order reaction are:
(a) mol^-1 litre s^-1
(b) mol litre^-2 s^-1
(c) s^-1
(d) mol litre^-1 s^-1

Answer: (a) mol^-1 litre s^-1

Question 6.
The value of k for a reaction is 2.96 × 10^-30 s^-1. What is the order of the reaction?
(a) Zero
(b) 3
(c) 2
(d) 1

Answer: (d) 1

Question 7.
A reaction is found to be of second order with respect to concentration of carbon monoxide. If concentration of carbon monoxide is doubled, the rate of reaction will
(a) triple
(b) increase by a factor of 4
(c) double
(d) remain unchanged

Answer: (b) increase by a factor of 4

Question 8.
If the concentrations are expressed in mol litre^-1 and time in s, then the units of rate constant for the first-order reactions are
(a) mol litre^-1 s^-1
(b) mol^-1 litre s^-1
(c) s^-1
(d) mol² litre^-2 s^-1

Answer: (c) s^-1

Question 9.
The half life of a first order reaction having rate constant 200 s^-1 is
(a) 3.465 × 10^-2 s
(b) 3.465 × 10^-3 s
(c) 1.150 × 10^-2 S
(d) 1.150 × 10^-3 S

Answer: (b) 3.465 × 10^-3 s

Question 10.
The rate of a reaction is 1.209 × 10^-4L² mol^-2s^-1. The order of the reaction is:
(a) zero
(b) first
(c) second
(d) third

Answer: (d) third

Question 11.
A catalyst increases the rate of a reaction by
(a) increasing threshold energy
(b) increasing activation energy
(c) activating the reactants
(d) lowering activation energy

Answer: (d) lowering activation energy

Question 12.
Time required for 100% completion of a zero order reaction is:
(a) t_100% = a/k
(b) t_100% = a.k
(c) t_100% = a/2k
(d) None of these

Answer: (a) t_100% = a/k

Question 13.
Arrhenius equation is represented by:
(a) k = Ae^Ea/RT
(b) k = Ae^-Ea/RT
(c) t1/2 = 0.693/k
(d) None of these

Answer: (b) k = Ae^-Ea/RT

Question 14.
The overall order of a reaction, which has the rate expression: Rate = AC[A]^1/2[B]^3/2 is:
(a) First order
(b) Second order
(c) Third order
(d) Zero order

Answer: (b) Second order

Question 15.
If half life period of a first order reaction is 100 seconds. Then rate constant will be:
(a) 6.93 × 10^-3 second^-1
(b) 6.93 × 10^-2 second^-1
(c) 0.693 second^-1
(d) 6.93 second^-1

Answer: (a) 6.93 × 10^-3 second^-1

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