Q21 of 36 Page 1

(i) Out of (CH3)3C–Br and (CH3)3C–I, which one is more reactive towards SN1 and why?

(ii) Write the product formed when p-nitrochlorobenzene is heated with aqueous NaOH at 443 K, followed by acidification.


(iii) Why dextro and laevo – rotatory isomers of Butan-2-ol are difficult to separate by fractional distillation?


(i) (CH3)3C–I

Explanation: In SN1 reactions, reactivity depends on the stability of carbocation. Carbocation is same here, therefore, we will see the reactivity of leaving group. I- is a better leaving group because of being good nucleophile. Hence Sn1 reaction is faster in (CH3)3-I



(ii) When p-nitro-chloro benzene is heated with aq. NaOH at 443 K,then NO2 will replace Cl as a substitute. Then, after acidification due OH will replace NO2 as a substitute.



(iii) dextro and laevo rotatory isomers of butan-2-ol are difficult to separate by fractional distillation because of no difference in boiling points of these two rotatory isomers.


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(i) Nylon-6,6


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OR


(i)


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(i) What type of drug is used in sleeping pills?

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An aromatic compound ‘A’ on heating with Br2 and KOH forms a compound ‘B’ of molecular formula C6H7N which on reacting with CHCl3 and alcoholic KOH produces a foul smelling compound ‘C’. Write the structures and IUPAC names of compounds A, B and C.

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Complete the following reactions:


OR


Write chemical equations for the following reactions:


(i) Propanone is treated with dilute Ba(OH)2.


(ii) Acetophenone is treated with Zn(Hg)/Conc. HCl


(iii) Benzoyl chloride is hydrogenated in presence of Pd/BaSO4.