Q20 of 26 Page 1

(a) Why is bithional added to soap?

(b) What is the tincture of iodine ? Write its one use.


(c) Among the following, which one acts as a food preservative ?


Aspartame, Aspirin, Sodium Benzoate, Paracetamol

(a) Bithional added to soaps to impart antiseptic properties and to reduce the odour produced by bacterial decomposition of organic matter on the skin


(b) Tincture of iodine, iodine tincture, or weak iodine solution is an antiseptic. It is usually 2–7% elemental iodine, along with potassium iodide or sodium iodide, dissolved in a mixture of ethanol and water. Tincture solutions are characterized by the presence of alcohol.


(c) Sodium benzoate - is a food preservative


More from this chapter

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18

(A), (B) and (C) are three non-cyclic functional isomers of a carbonyl compound with molecular formula C 4H 8O . Isomers (A) and (C) give positive Tollen’s test whereas isomer (B) does not give Tollen’s test but gives positive Iodoform test. Isomers (A) and (B) on reduction with Zn(Hg)/conc. HCl give the same product (D).

(a) Write the structures of (A), (B), (C) and (D).


(b) Out of (A), (B) and(C) isomers, which one is least reactive towards addition of HCN?

 19

Write the structure of the main products in the following reactions:

 21

Define the following with an example of each :

(a) Polysaccharides


(b) Denatured protein


(c) Essential amino acids


OR


(a) Write the product when D-glucose reacts with conc. HNO3.


D-glucose + HNO3→


(b) Amino acids show amphoteric behaviour. Why?

 22

(a) Write the formula of the following coordination compound : Iron(III) hexacyanoferrate (II)

(b) What type of isomerism is exhibited by the complex


(c) Write the hybridisation and number of unpaired electrons in the complex [CoF6 ]3- . (Atomic No. of Co = 27)