Class XII Assignment for Unit Test 2

Assignment for Unit Test-ii, Std-xii

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Last Date for Submission-05-09-2019

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Topic:Chemical Kinetics

1.For a reaction A + B ® Product, the rate low is given by r = k[A]½ [B]2. What is the order of the reaction ?

2.The rate of a particular reaction quadruples when the temperature changes from 293 K to 313 K.Calculate activation energy.

3.If the decomposition of nitrogen oxide as follows a first order kinetics

  • Calculate the rate constant for a 0.05M solution if the instantaneous rate
    is 1.5 ´ 10–6 mol/l/s ?   
  • What concentration of N2O5 would give a rate of 2.45 ´ 10–5 mol L–1 S–1?           

4.The decomposition of hydrocarbon follows the equation                                                         K = (4.5 ´ 1011S–1) e–28000k/T.      Calculate Ea.

5. A reaction is of second order with respect to a reactant. How is the rate of reaction affected if the conc. of the reactant is reduced to half? What is the unit of rate constant for such a reaction?

Topic:Alcohols,Phenols and Ethers

6. How is phenol obtained from aniline ?

7.Ethanol has higher boiling point than methoxy methane. Give reason.

8. How will you convert :

 (i) Phenol to cyclohexanol (ii) Benzene chloride to benzyl alcohol (iii) Anisole to phenol

9. Phenol, when it first reacts with concentrated sulphuric acid, forms Y. The compound, Y is reacted with concentrated nitric acid to form Z. Identify Y and Z and explain why phenol is not converted commercially to Z by reacting it with conc. HNO3 .

10. Ethers are relatively inert. Justify.

11. Lower alcohols are soluble in water, higher alcohols are not. Why ?

12. Give equations of the following reactions :

(i) Oxidation of propan-1-al with alkaline KMnO4 solution.

(ii) Bromine in CS2 with phenol.

(iii) Treating phenol with chloroform in presence of aqueous NaOH.

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