CBSE Class 12 Chemistry Chemical Kinetics Notes Set E

CBSE Class 12 Chemistry notes and questions for Chemical Kinetics Part C. Learning the important concepts is very important for every student to get better marks in examinations. The concepts should be clear which will help in faster learning. The attached concepts made as per NCERT and CBSE pattern will help the student to understand the chapter and score better marks in the examinations.



1. Define the term ‘rate of reaction’.

2. Mention the units of rate of reaction.

3. Express the rate of reaction in terms of Br– (aq) as reactant and Br2 (aqas product for the reaction :

5 Br–(aq) + Br(aq) + 6H+ (aq) →3 Br2(aq) + 3H2O(/)

4. For a chemical reaction represented by R →P the rate of reaction is denoted by

-Δ[R] / Δt OR  +Δ[P] / Δt 

Why a positive sign (+) is placed before Δ[P] / Δt and negative sign(-) before  Δ[R] /  Δt? 

5. Express the rate of reaction in terms of disappearance of hydrogen and appearance of ammonia in the given reaction.

N2(g) + 3 H2 (g) →2NH3 (g)

6. Why rate of reaction does not remain constant throughout?

7. Write the unit of first order rate constant of a gaseous reaction if the partial pressure of gaseous reactant is given in bar.

8. For a zero order reaction :

R →P, the change in concentration of reactant w.r.t. time is shown by following graph.


9. What will be the order of reaction, if the rate of reaction does not depend

on the concentration of any of the reactant.

10. For the elementary step of a chemical reaction :

H2 + I2 2HI

rate of reaction [H2] [I2]

What is the (i) molecularity and (ii) order of the reaction.

11. For a chemical reaction A B. The rate of the reaction is given as Rate = k [A]n, the rate of the above reaction quadruples when the concentration of A is doubled. What is the value of n? [Ans. : n = 2]

12 Mention one example of zero order reaction.

13. What is the value of the order of reaction of radioactive decay? [Ans. : First order]

*14. Express the relation between the half life period of a reactant and initial concentration for a reaction of nth order.

[Ans : t½ α 1 / A0n–1 

*15. A reaction is 50% complete in 2 hours and 75% complete in 4 hours. What

is the order of reaction? Ans : [First order]

16. Suggest an appropriate reason for the observation : “On increasing

temperature of the reacting system by 10 degrees, the rate of reaction

almost doubles or even sometimes becomes five folds.”

*17. For a chemical reaction, activation energy is zero and at 300K rate constant

is 5.9 × 10–5 s–1, what will be the rate constant at 400K?

[Ans. : 5.9

Please click the link below to download pdf file for CBSE Class 12 Chemistry notes and questions for Chemical Kinetics Part C.



Click to View or Download pdf file
Click for more Chemistry Study Material

Latest NCERT & CBSE News

Read the latest news and announcements from NCERT and CBSE below. Important updates relating to your studies which will help you to keep yourself updated with latest happenings in school level education. Keep yourself updated with all latest news and also read articles from teachers which will help you to improve your studies, increase motivation level and promote faster learning

CBSE Decision on Board Exam 2020

The Class 10 and 12 exams are cancelled, and results for both 10th and 12th would be declared by July 15 based on internal exams. CBSE Class 12 students would have the option to appear for the exams at a later date. CBSE has a scheme in which marks scored in past 3...

Procedure for correction in Name and Date of Birth

Procedure for correction in Name and Date of Birth in CBSE records Name Change: Applications regarding changes in name or surname of candidates will be considered provided the changes have been admitted by the Court of law and notified in the Government Gazette before...

Class 12 Board Exams Datesheet Announced

CBSE has announced the datesheet of the remaining class 12 board exams, see below:  

Board Cancelled Official CBSE Statement

Keeping in view the requests received from various State Governments and the changed circumstances as on date, following has been decided- 1. Examinations for classes X and XII which were scheduled from 1st July to 15th, 2020 stand cancelled. 2. Assessment of the...

TV Channels for Students by CBSE

In enhancing the students studying part, the Government is planning to introduce one standard one channel plan. The lockdown in India has adversely collapsed all the operations including schools, colleges, and workplaces with unanticipated setbacks. On behalf of the...

Board Exams Class 10 and 12 Notification by CBSE

Because of the prevailing condition of spread of COVID-19 pandemic in the country, special efforts are required for conducting examinations in a safe manner. As a number of students have shifted from the district of their school to some other district in the country,...

Studies Today