Q22 of 26 Page 1

How do you convert:

(i) Chlorobenzene to toluene


(ii) Bu-1-ene to but-2-ene


(iii) Ethanol to ethyl iodide


OR


What happens when:


(i) n-butyl chloride is treated with alcoholic KOH


(ii) 2-chloropropane is treated with sodium in presence of dry ether


(iii) Chlorobenzene is treated with in the presence of anhydrous .


Write the chemical equations involves in the above reactions.


Option (i) Wurtz Fittig reaction can be used to convert Chlorobenzene to toluene by making it react to sodium in presence of methyl chloride will give you toluene.


This reaction also gives intramolecular products as ethane is found as a by-product.


Option (ii)


But-1-ene can be reduced by addition of HBr which will undergo Markovnikov’s addition forming 2-bromobutane which on treatment with alcoholic KOH undergoes Saytzeff’s elimination to give but-2-ene.



Option (iii)


Alcohols when treated with halogen halides give their corresponding halogen derivative. Thus treatment of ethanol with hydrogen iodide will give ethyl iodide.



OR


Option (i)


When n-butylchloride is treated with alcoholic KOH it undergoes β-elimination to give but-1-ene.



NOTE: The hydride shift can be considered as an alternative due to higher stability of 2° carbocation, but the energy required to do the 1,2-hydride shift is not sufficient so the 2° carbocation is not considered.


Option (ii)


When 2-chloropropane is treated with Na in dry ether it undergoes Wurtz reaction to give 2,3-dimethyl butane as a major product.



Option (iii)


When Chlorobenzene is treated with methyl chloride in presence of anhydrous ALCl3 it undergoes Friedel Crafts alkylation which facilitates electrophilic substitution of CH3 on the benzene ring to give o-chlorotoulene and p-chlorotoulene as a product.



More from this chapter

All 26 →
20

(i) Write the name of Monosaccharides which are obtained after the hydrolysis of lactose

(ii) What type of bonding is responsible for the stability of α – helix?


(iii) Write the difference between nucleotide and nucleoside.


21

A. For the complex . Write the hybridization, magnetic character and spin of the complex. ( Z = 27)

B. Why is the complex more stable than the complex ?


23

Due to hectic and busy schedule, Mr. Singh started taking junk food in the lunch break and slowly became habitual of eating food irregularly to excel in his field. One day during meeting he felt severe chest pain and fell down. Mr. Khanna a close friend of Mr. Singh took him to doctor immediately. The doctor diagnosed that Mr. Singh was suffering from acidity and prescribed some medicines. Mr. Khanna advised him to eat homemade food and change his lifestyle by doing yoga, Meditation and some physical exercise. Mr. Singh followed his friend’s advice and after few days he started feeling better. After reading the above passage answer the following:

A. What are the values (at least two) displayed by MR. Khanna?


B. What are antacids? Give examples.


C. Would it be advisable to take antacids for a long period of time? Give reasons.


24

A. Calculate ΔG° and log Kc for the following reaction at 298 K:


Given:


B. Using the values of A and B, predict which is better for coating the surface of iron to prevent corrosion and give reasons.


,


OR


A. The conductivity of 0.001 mol L-1 solution of CH3COOH is 3.905× 10-5 S cm-1. Calculate its molar conductivity and degree of dissociation (α).


Given: and



B. What type of battery is dry cell? Write the overall reaction occurring in dry cell.