PCl₅ reacts with ethanol to form chloromethane. However, with phenol, it does not give chlorobenzene but gives triphenylphosphate. Explain.

Explain why alcohols do not react with NaBr but H₂SO₄ is added they form alkyl bromides.

Although both allyl alcohol and 1-propanol are primary alcohols,they can still be distinguished by Lucas reagent. Explain how?

Gasoline is being used worldwide for running automobile, aeroplane etc. Due to the presence of nitrogen and sulphuric compounds in gasoline, the exhaust gases contain oxides of nitrogen and sulphur which are major pollutants in the environment in contrast, ethanol is a much cleaner fuel because it produces only CO₂ and Hp. Now answer the following questions:
(a) Besides being a cleaner fuel, what are the other advantages of using ethanol as a fuel in automobile?  
(b) What are the disadvantages of using ethanol as a fuel? What are the value associated with its use?

Miss Usha was asked to synthesize alcohol by acidic hydration of l-butene. She was unaware of the fact that the vessel she used had some coating of a  metal, and in addition to alcohol, compound X was I isolated X forms bisulphate compound as well as 2, 4-dinitrophenylhydrazone. Separation of alcohol could be made by physical as well as by chemical methods.
(i) How are alcohol and Xformed? 
(ii) Can alcohol and Xgive iodoform test? 
(iii) Give different methods of separation? 
(iv) What value did Miss. Usha lack?

Mohan heard a lot of noise and weeping in nearby jhuggis he look courage and went to enquire what had happened. He found that some people has taken spurious alcohol containing methanol and were crying with pain and were complaining of loss of eyesight. He immediately hired an auto rickshaw and packed it with 4 persons who has consumed spurious alcohol.
(i) How does methanol in drinking alcohol cause problem?
(ii) What treatment might the doctors have undertaken to save the patients?
(iii) What message would you give to the person who consumed spurious alcohol?

A teacher ordered ethanol for laboratory. She preferred denatured alcohol over absolute alcohol.
(i) Give reason for the decision taken by the teacher.
(ii) What value was kept in mind while taking the decision?

A compound A (C₄H₁₀O) is found to be soluble in concentrated sulphuric acid. (A) does not react with sodium metal or potassium permanganate. When (A) is heated with excess of HI, it gives a single alkyl halide. Deduce the structure of compound (A) and explain all the reactions involved.

An organic compound (A) on treatment with CHCl₃ and KOH gives two compounds B and C.Both B and C give the same product (D) when distilled with zinc dust.Oxidation of D gives E having molecular formula C₇H₆O₂.The sodium salt of E on heating with soda-lime gives F which may also be obtained by distilling A with zinc dust.Identify A to F

An organic compound (A) with molecular formula C₆H₆O gives a characteristic colour with aqueous FeCl₃ solution. When (A) is treated with CO₂ and NaOH at 410K under pressure, it gives compound (B) which upon acidification gives compound (C). Compound (C) reacts with acetyl chloride to give (D) which is a popular pain killer, Deduce the structures of (A), (B), (C) and (D) and explain all the reactions involved.