Explain the cleansing action of soaps.
Cleansing action of soaps : Soaps contain two parts, a large hydrocarbon which is a hydrophobic (water repelling) and a negative charged head, which is hydrophillic (water attracting). In solution water molecules being polar in nature, surround the ions & not the organic part of the molecule. When a soap is dissolved in water the molecules gather together as clusters, called micelles. The tails stick inwards & the head outwards. The hydrocarbon tail attaches itself to oily dirt. When water is agitated, the oily dirt tends to lift off from the dirty surface & dissociates into fragments. The solution now contains small globules of oil surrounded detergent molecules. The negatively charged heads present in water prevent the small globules from coming together and form aggregates. Thus the oily dirt is removed from the object.
Which of the following statements are correct about barbiturates?
(a) Hypnotics or sleep producing agents.
(b) These are tranquilizers.
(c) Non-narcotic analgesics.
(d) Pain reducing without disturbing the nervous system.
While antacids and antiallergic drugs interfere with the function of histamines, why do these not interfere with the function of each other?
Assertion (A): Receptor proteins show selectivity for one chemical messenger over the other.
Reason (R): Chemical messenger binds to the receptor site and inhibits its natural function.
Assertion (A): Preservative are added to food items.
Reason (R): Preservatives inhibit the growth of microorganisms.
Which of the following are anionic detergents?
(a) Sodium salts of sulphonated long chain alcohol.
(b) Ester of stearic acid and polyethylene glycol.
(c) Quaternary ammonium salt of amine with acetate ion.
(d) Sodium salts of sulphonated long chain hydrocarbons.
Which of the following are not used as food preservatives?
(a) Table salt (b) Sodium hydrogen carbonate
(c) Cane sugar (d) Benzoic acid
What happens when the bond formed between an enzyme and an inhibitor is a strong covalent bond?
Synthetic detergents have advantage over usual soaps as far as cleansing power is concerned. But use of synthetic detergents over a long time creates environmental pollution. How can the pollution caused by synthetic detergents be minimized? Classify the detergents according to their chemical nature.
What are enzyme inhibitors? Classify them on the basis of their mode of attachments on the active site of enzymes. With the help of diagrams explain how do inhibitors inhibit the enzymatic activity.
Ckemistnj in Evenjdai] Life 325
With the help of an example explain how do tranquilizers control the feeling of depression?
In what respect do prontosil and Salvarsan resemble? Is there any resemblance between azo dye and prontosil? Explain.
Which of the following compounds are administered as ant-acids?
(a) Sodium carbonate (b)Sodium Hydrogen carbonate
(c)Aluminium carbonate (d)Magnism Hydroxide
Assertion (A): Receptors are crucial to body's communication process. Reason (R): Receptors are proteins.
Compounds with antiseptic properties are
(a) CHCl, (b) CHI3
(c) Boric acid (d) 0.3 ppm aqueous solution of Cl2
Aspirin is pain relieving antipyretic drug but can be used to prevent heart attack. Explain.
Both antacids and antiallergic drugs are antihistamines but they cannot replace each other. Explain why?
Explain why sometimes foaming is seen in river water near the place where sewage water is poured after treatment?
Between sodium hydrogen carbonate and magnesium hydroxide which is a better antacid and why?