CBSE Class 12 Chemistry Chemical Kinetics Quiz 2

1. Fora unimolecular reaction

A the order and molecuiarity of the slowest step are equal to one B molecuiarity of the reaction can be zero, one or two C molecuiarity of the reaction can be determined only experimentally D more than one reacting species are involved in one step

2. The overall rate of a reaction is governed by

A the rate of fastest intermediate’step B the sum total of the rates of all intermediate steps C the average of the rates of all the intermediate steps D the rate of slowest intermediate step

3. The order of reaction is decided by

A temperature B mechanism of reaction as well as relative concentration of reactants C molecularity D pressure

4. Rate constant in case of first order reaction is

A inversely proportional to the concentration units B independent of concentration units C directly proportional to concentration units D inversely proportional to the square of concentration units

5. Half life period of a first order reaction is 10 min. What percentage of the reaction will be completed in 100 min?

A 25% B 50% C 99.9% D 75%

6. In pseudo unimolecular reactions

A both the reactants are present in low concentration B both the reactants are present in same concentration C one of the reactant is present in excess D one of the reactant is non-reactive

7. A first order reaction takes 40 min for 30% decomposition. What will be t

A 77.7 min B 52.5 min C 46.2 min D 22.7 min

8. A first order reaction has a rate constant 1.15 × 10

9. Radioactive disintegration is an example of

A zero order reaction B first order reaction C second order reaction D third order reaction

10. A plot of log (a – x) against time t is a straight line. This indicates that the reaction is of

A zero order B first order C second order D third order