CBSE Class 12 Chemistry Chapter 4 (Chemical Kinetics) | Homi Institue

CBSE Class 12 Chemistry Chapter 4 (Chemical Kinetics) By Homi Institute

1. CBSE Class 12 Chemistry Chemical Kinetics

2. (colliding atoms)

3. Formic acid

4. Also, at what rate O 2 will produce during this time?

5. Rate law or rate expression is the expression in which reaction rate is given in terms of molar concentration of reactants with each term raised to some power, which may or may not be same as the stoichiometric coefficient of the reacting species in a balanced chemical equation.

6. Rate law for any reaction cannot be predicted by merely looking at the balanced chemical equation, i.e., theoretically but must be determined experimentally . Ex -

8. Answer – 2,0,2 Answer – © Answer - B

9. Answer - D

10. For Elementary reaction - The number of reacting species (atoms , ions or molecules) taking part in an elementary reaction, which must collide simultaneously in order to bring about a chemical reaction is called molecularity of a reaction. For Complex reaction

11. First order gas phase reaction

12. Pseudo First Order Reaction

13. Temperature Dependence of the Rate of a Reaction It has been found that for a chemical reaction with rise in temperature by 10°, the rate constant is nearly doubled. The temperature dependence of the rate of a chemical reaction can be accurately explained by Arrhenius equation. k measured in joules/mole

14. Activation energy is defined as the minimum amount of extra energy required by a reacting molecule to get converted into product. It can also be described as the minimum amount of energy needed to activate or energize molecules or atoms so that they can undergo a chemical reaction or transformation. The peak of the curve corresponds to the most probable kinetic energy, i.e ., kinetic energy of maximum fraction of molecules. There are decreasing number of molecules with energies higher or lower than this value .

15. When the temperature is raised, the maximum of the curve moves to the higher energy value and the curve broadens out, i.e., spreads to the right such that there is a greater proportion of molecules with much higher energies. The area under the curve must be constant since total probability must be one at all times.

16. h igh as times.   A catalyst does not alter Gibbs energy, ΔG of a reaction. It catalyses the spontaneous reactions but does not catalyse non spontaneous reactions . Proper alignment Proper alignment I mproper alignment I mproper alignment