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Q.2 Fill in the blanks with suitable words.(i) The rate of an endothermic reaction with the increase in temperature.(ii) All radioactive disintegration nuclear reactions are of order(iii) For a fast reaction the rate constant is relatively and half - life is(iv) The second order reaction becomes if one of the reactants is in large excess.(v) Arrhenius equation can be used to find out of a reaction.

### Q.2 Fill in the blanks with suitable words.(i) The rate of an endothermic reaction with the increase in temperature.(ii) All radioactive disintegration nuclear reactions are of order(iii) For a fast reaction the rate constant is relatively and half - life is(iv) The second order reaction becomes if one of the reactants is in large excess.(v) Arrhenius equation can be used to find out of a reaction.

Q5. The rate of a chemical reaction with respect to products is written with positive sign but with respect to reactants is written with a negative sign. Explain it with reference to the following hypothetical reaction.\[\mathrm{aA}+\mathrm{bB} \rightarrow \mathrm{cC}+\mathrm{dD}\]

### Q5. The rate of a chemical reaction with respect to products is written with positive sign but with respect to reactants is written with a negative sign. Explain it with reference to the following hypothetical reaction.\[\mathrm{aA}+\mathrm{bB} \rightarrow \mathrm{cC}+\mathrm{dD}\]

Q21. Some reactions taking place around room temperature have activation energies around 50 \mathrm{~kJ} \mathrm{mol}^{-1} .(i) What is the value of the factor e^{\frac{-\mathrm{E}}{\mathrm{RT}}} at 25^{\circ} \mathrm{C} ?

### Q21. Some reactions taking place around room temperature have activation energies around 50 \mathrm{~kJ} \mathrm{mol}^{-1} .(i) What is the value of the factor e^{\frac{-\mathrm{E}}{\mathrm{RT}}} at 25^{\circ} \mathrm{C} ?

Q7. Differentiate between(i) Rate and rate constant of a reaction

### Q7. Differentiate between(i) Rate and rate constant of a reaction

Q.1 Multiple choice questions.(ii) If the rate equation of a reaction 2 \mathrm{~A}+\mathrm{B} \rightarrow products is rate =k[\mathrm{~A}]^{2}[\mathrm{~B}] and \mathrm{A} is present in large excess then order of reaction isa) 1(b) 2(c) 3(d) none of these

### Q.1 Multiple choice questions.(ii) If the rate equation of a reaction 2 \mathrm{~A}+\mathrm{B} \rightarrow products is rate =k[\mathrm{~A}]^{2}[\mathrm{~B}] and \mathrm{A} is present in large excess then order of reaction isa) 1(b) 2(c) 3(d) none of these

Q.1 Multiple choice questions.(iii) The rate of reactiona) increases as the reaction proceeds.b) decreases as the reaction proceeds.c) remains the same as the reaction proceeds.d) may decrease or increase as the reaction proceeds.

### Q.1 Multiple choice questions.(iii) The rate of reactiona) increases as the reaction proceeds.b) decreases as the reaction proceeds.c) remains the same as the reaction proceeds.d) may decrease or increase as the reaction proceeds.

Q11. The rate determining step of a reaction is found out from the mechanism of that reaction. Explain it with few examples.

### Q11. The rate determining step of a reaction is found out from the mechanism of that reaction. Explain it with few examples.

Q16. Define the following terms and give examples(vi) Enzyme catalysis

### Q16. Define the following terms and give examples(vi) Enzyme catalysis

Q11. The rate determining step of a reaction is found out from the mechanism of that reaction. Explain it with few examples.

### Q11. The rate determining step of a reaction is found out from the mechanism of that reaction. Explain it with few examples.

Q.1 Multiple choice questions.(v) The unit of the rate constant is the same as that of the rate of reaction in(a) first order reaction. (b) second order reaction.(c) zero order reaction. (d) third order reaction.

### Q.1 Multiple choice questions.(v) The unit of the rate constant is the same as that of the rate of reaction in(a) first order reaction. (b) second order reaction.(c) zero order reaction. (d) third order reaction.

Q18. What are enzymes? Give examples in which they act as catalyst. Mention the characteristics of enzyme catalysis.

### Q18. What are enzymes? Give examples in which they act as catalyst. Mention the characteristics of enzyme catalysis.

Q14. The collision frequency and the orientation of molecules are necessary conditions for determining the proper rate of reaction. Justify the statement.

### Q14. The collision frequency and the orientation of molecules are necessary conditions for determining the proper rate of reaction. Justify the statement.

In the thermal decomposition of \mathrm{N}_{2} \mathrm{O} at 760{ }^{\circ} \mathrm{C} the time required to decompose half of the reactant was 255 seconds at the initial pressure of 290 \mathrm{~mm} \mathrm{Hg} and 212 seconds at the initial pressure of 360 \mathrm{mmHg} . Find the order of this reaction.

### In the thermal decomposition of \mathrm{N}_{2} \mathrm{O} at 760{ }^{\circ} \mathrm{C} the time required to decompose half of the reactant was 255 seconds at the initial pressure of 290 \mathrm{~mm} \mathrm{Hg} and 212 seconds at the initial pressure of 360 \mathrm{mmHg} . Find the order of this reaction.

Q17. Briefly describe the following with examples(iii) A finely divided catalyst may prove more effective.

### Q17. Briefly describe the following with examples(iii) A finely divided catalyst may prove more effective.

Q8. Justify the following statements(vi) The sum of the coefficients of a balanced chemical equation is not neessarily important to give the order of a reaction.

### Q8. Justify the following statements(vi) The sum of the coefficients of a balanced chemical equation is not neessarily important to give the order of a reaction.

Q8. Justify the following statements(ii) The reaction rate decreases every moment but rate constant k of the reation is a constant quantity under the given conditions.

### Q8. Justify the following statements(ii) The reaction rate decreases every moment but rate constant k of the reation is a constant quantity under the given conditions.

Q17. Briefly describe the following with examples(iv) Equilibrium constant of a reversible reaction is not changed in the presence of a catalyst.

### Q17. Briefly describe the following with examples(iv) Equilibrium constant of a reversible reaction is not changed in the presence of a catalyst.

Calculate the half-life period of the following reaction when the initial concentration of HI is 0.05 \mathrm{M} . 2 \mathrm{HI}(\mathrm{g}) \square \mathrm{H}_{2}(\mathrm{~g})+\mathrm{I}_{2}(\mathrm{~g}) The value of rate constant \mathrm{k}=0.079 \mathrm{dm}^{3} \mathrm{~mol}^{-1} \mathrm{~s}^{-1} at 508{ }^{\circ} \mathrm{C} and rate expression isRate =\mathrm{k}[\mathrm{HI}]^{2}

### Calculate the half-life period of the following reaction when the initial concentration of HI is 0.05 \mathrm{M} . 2 \mathrm{HI}(\mathrm{g}) \square \mathrm{H}_{2}(\mathrm{~g})+\mathrm{I}_{2}(\mathrm{~g}) The value of rate constant \mathrm{k}=0.079 \mathrm{dm}^{3} \mathrm{~mol}^{-1} \mathrm{~s}^{-1} at 508{ }^{\circ} \mathrm{C} and rate expression isRate =\mathrm{k}[\mathrm{HI}]^{2}

Q.1 Multiple choice questions.(ii) If the rate equation of a reaction 2 \mathrm{~A}+\mathrm{B} \rightarrow products is rate =k[\mathrm{~A}]^{2}[\mathrm{~B}] and \mathrm{A} is present in large excess then order of reaction isa) 1(b) 2(c) 3(d) none of these

### Q.1 Multiple choice questions.(ii) If the rate equation of a reaction 2 \mathrm{~A}+\mathrm{B} \rightarrow products is rate =k[\mathrm{~A}]^{2}[\mathrm{~B}] and \mathrm{A} is present in large excess then order of reaction isa) 1(b) 2(c) 3(d) none of these

Q7. Differentiate between(iii) Fast step and the rate determining step

### Q7. Differentiate between(iii) Fast step and the rate determining step

Q17. Briefly describe the following with examples(ii) A very small amount of a catalyst may prove sufficient to carry out a reaction.

### Q17. Briefly describe the following with examples(ii) A very small amount of a catalyst may prove sufficient to carry out a reaction.

Q20. A study of chemical kinetics of a reaction\begin{tabular}{|c|c|c|}\hline [\mathrm{A}] & { [\mathrm{B}] } & Rate \\\hline 1.00 & 0.15 & 4.2 \times 10^{-6} \\ 2.00 & 0.15 & 8.4 \times 10^{-6} \\ 1.00 & 0.2 & 5.6 \times 10^{-6} \\\hline\end{tabular}gave the following data at 25^{\circ} \mathrm{C} . Calculate the rate law.

### Q20. A study of chemical kinetics of a reaction\begin{tabular}{|c|c|c|}\hline [\mathrm{A}] & { [\mathrm{B}] } & Rate \\\hline 1.00 & 0.15 & 4.2 \times 10^{-6} \\ 2.00 & 0.15 & 8.4 \times 10^{-6} \\ 1.00 & 0.2 & 5.6 \times 10^{-6} \\\hline\end{tabular}gave the following data at 25^{\circ} \mathrm{C} . Calculate the rate law.

Q17. Briefly describe the following with examples(v) A catalyst is specific in its action.

### Q17. Briefly describe the following with examples(v) A catalyst is specific in its action.

Q8. Justify the following statements(v) The radioactive decay is always a first order reaction.

### Q8. Justify the following statements(v) The radioactive decay is always a first order reaction.

Q.1 Multiple choice questions.(i) In zero order reaction the rate is independent ofa) temperature of reaction.(b) concentration of reactantsc) concentration of products(d) none of these

### Q.1 Multiple choice questions.(i) In zero order reaction the rate is independent ofa) temperature of reaction.(b) concentration of reactantsc) concentration of products(d) none of these

Q5. The rate of a chemical reaction with respect to products is written with positive sign but with respect to reactants is written with a negative sign. Explain it with reference to the following hypothetical reaction.\[\mathrm{aA}+\mathrm{bB} \rightarrow \mathrm{cC}+\mathrm{dD}\]

### Q5. The rate of a chemical reaction with respect to products is written with positive sign but with respect to reactants is written with a negative sign. Explain it with reference to the following hypothetical reaction.\[\mathrm{aA}+\mathrm{bB} \rightarrow \mathrm{cC}+\mathrm{dD}\]

Q8. Justify the following statements(v) The radioactive decay is always a first order reaction.

### Q8. Justify the following statements(v) The radioactive decay is always a first order reaction.

Q12. Discuss the factors which influence the rates of chemical reactions.

### Q12. Discuss the factors which influence the rates of chemical reactions.

Q17. Briefly describe the following with examples(iii) A finely divided catalyst may prove more effective.