Two mole of an ester (A) are condensed in presence of sodium ethoxide to give a `beta-`keto ester (B) and ethanol. On heating in an acidic solution (B) gives ethanol and `beta-`keto acid (C). On decarboxylation (C) give 3-pentanone.
Identify (A),(B) and (C).

Zinc on reaction with NaOH gives a salt (A) along with a gas (B). (A) on reaction with H_(2)S gas gives a white precipitate (C ). Identify (A), (B) and (C ).

CH_(3) CO_(2) C_(2) H_(5) on reaction with sodium ethoxide in ethanol gives A , which on heating in the presence of acid gives B compound B is

CaCO_3 on heating gives a white solid (A) and a gas (B), (A) on heating with carbon gives a solid (C) and a gas (D), (C) on hydrolysis glves a gas (E) and a solid (F) Identify (A), (B), (C), (D) , (E) and (F) .

Boric acid on heating at 100^@ C , gives (X) . (X) on heating at 160^@ C gives (Y) and (Y) on heating at red hot gives (Z) . Identify (X),(Y) and (Z) .

Magnesium on heating in air gives (A) and (B) . On reaction with water (B) gives a colourless gas (C ).(C ) when passed through CuSO_(4) solution, gives a blue coloured solution (D) . Identify (C ) and (D) .

Identify (A) to ( C) . (a) An inorganic iodide (A) on heating with a solution of KOH gives a gas (B) and the solution of a compound ( C) .

An aqueous solution of salt (A) gives a give a white precipitate ( B) with sodium chloride solution . Compound ( B) dissolves in hot water and the solution on treatment with sodium iodide give a yellow precipitate ( D) ,. and on passing H_2 S through solution ( B) gives a black ppt . (C) . Compound (A) does not give any gas with dil HCl , but liberates a reddish brown gas on heating identify compounds (A), (B), ( C) , and (D) .

Compound (A), C_(8)H_(6)NOBr , is optically active. Reduction of (A) gives (B) which reacts with nitrouos acid to form (C), dihydric alcohol. Benzene sulphonyl chloride reacts with (B) to give a product soluble in NaOH. Hydrolysis of (A) gives (D) which is an optically active acid. (A) does not give any precipitate with aqueous AgNO_(3) . Controlled oxidation of (A) gives monobromo benzoic acid. Compound (A) on reaction with Br_(2)//Fe gives only one compound. Identify (A), (B), (C), and (D).

alkali metal (A) on flame test gives a crimson red colour to the Bunsen flame. (A) on heating in air gives compound (B), and (B) further on hydrolysis gives (C ) and gas (D). Gas (D) with Nessler's reagent gives a brown precipitate Identify (A), (B), (C ) and (D).