(a) Discuss Williamson method to prepare ethers. Give the limitations of this method.
(b) Under what conditions do ethers form oxonium salts?
(c ) Give four important uses of diethyl ether.

under what conditions do ethers from oxonium salts?

What are ethers? How are they classified ? Give two methods by which diethyl ether can be prepared from ethanol. Discuss its important properties.

(a) What do you understand by the term potential energy ? (b) State two factors which determine potential energy of a body. (c) Give four examples of potential energy.

Write the structural formula of diethyl ether. (a) Give the IUPAC name of CH_(3)-O-CH_(3) . (b) Indicate a method by which ethanol may be converted to diethyl ether.

(a) Explain why cleavage of phenyl ethers with HBr always produces phenol and alkyl bromides and not bromobenzene and alkanols. (b) Give reasons for the following: (i) The dipole moment of diethyl ether (1.18D) is lower than that of water (1.84D). (ii) The C-O-C bond angle in ethers is higher than H-O-H angle in water though oxygen is sp3 hybridized in both the cases. (iii) Dimethyl ether is completely miscible with water but diethyl ether is soluble in water to a small extent.

(a) Give one method each for the industrial preparation of: (i) ethyl alcohol (ii) phenol (b) What is the action of each of the following on phenol? (i) HNO_(3) in presence of conc. H_(2)SO_(4) (ii) Br_(2) in presence of CS_(2) at 278K (iii) CO_(2) at 400K and 4/7 atm. Pressure.

Preparation of ethers by acid dehydration of secondary or tetiary alcohols is not a suitable method. Give reason.

An organic compound (A) C_(4)H_(9)Cl on reacting with aqueous KOH gives (B) and on reaction with alcoholic KOH gives (C ), which is also formed on passing the vapours of (B) over the heated copper. The compound (C ) readily decolourises bromine water. Ozonolysis of (C ) gives two compounds (D) and (E ). Compound (D) reacts with NH_(2)OH to give (F) and compound (E ) reacts with NaOH to have an alcohol (G) and sodium salt (H) of an acid. (D) can also be prepared form propyne on treatment with water in the presence of Hg^(2+) and H_(2)SO_(4) . Identify (A) to (H) with proper reasoning.

Three compounds A,B and C all have molecular formula C_(5)H_(8) All the compound rapidly decolourise Br_(2) in C Cl_(4) . All three give a position test with Baeyer's reagent. And all the three are soluble in cold conc. H_(2)SO_(4) . Compound A gives a precipitate when treated with ammonical AgNO_(3) solution. but compounds B and C do not compounds A and B both yield pentane (C_(5)H_(12)) when they are treated with excess H_(2) in the presence of Pt catalyst. Under these conditions, compound C absorbs only one mole of H_(2) and gives a product with the formula C_(5)H_(10) On oxidation with hot acidified KMnO_4, B gave acetic acid and CH_3CH_2COOH. Identify compounds A, B, and C.

(a) A colloidal sol is prepared by the given method in figure. What is the charge of AgI colloidal particles in the test tube ? How is the sol formed, represented? (b) Explain how the phenomenon of adsorption finds application in Heterogeneous catalysis. (c) Which of the following electroytes is the most effective for the coagulation of Fe(OH)_(3) sol which is a positively charged sol? NaCI, Na_(2)SO_(4), Na_(3)PO_(4)