1. Which one of the following polymers is widely used for making bullet proof material?
(a) Polyvinyl chloride
(b) Polyamides
(c) Polyethylene
(d) Polycarbonates
(d) Polycarbonates are the polymer widely used in making bullet proof material. Bullet proof glass is made by layering a polycarbonate material between pieces of ordinary glass in a process called lamination. A bullet fired will pierce the outside layer of the glass, but the layered polycarbonate glass material is able to absorb the bullet's energy and stop it. Polycarbonate panels are used for covering advertising posters, construction of office buildings for sound proofing and polycarbonate is also used for making bullet proof jackets.
2. The offending substance in the liquor tragedies leading to blindness etc. is
(a) ethyl alcohol
(b) amyl alcohol
(c) benzyl alcohol
(d) methyl alcohol
(d) Methyl alcohol is very dangerous. May be fatal or cause blindness if swallowed. Harmful, if inhaled or absorbed through skin. It cannot be made non poisonous. Some other harmful effects are results into irritation of skin, eyes and respiratory track. It can also effects central nervous system and liver.
3. The characteristic odour of garlic is due to
(a) a chloro compound
(b) a sulphur compound
(c) a fluorine compound
(d) acetic acid
(b) Allicin is an oily, yellow liquid, which gives garlic its characteristic odour which is due to the R–S(O)–S-R group. It also has a range of medical properties.
4. Which one of the following is an active component of oil of clove?
(a) Menthol
(b) Eugenol
(c) Methanol
(d) Benzaldehyde
(b) Oil of cloves, also known as Clove oil, is an essential oil obtained from the clove plant. It is a natural analgesic and antiseptic used primarily in dentistry for its main ingredient eugenol. The oil produced by cloves can be used in many things from flavouring medicine to remedies for bronchitis, common cold, a cough, fever, sore throat and tending to infections
5. Which one of the following was used as a chemical weapon in the first world war?
(a) Carbon monoxide
(b) Hydrogen cyanide
(c) Mustard gas
(d) Water gas
(c) The most effective gas of the first world war was mustard gas a vesicent, which was introduced by Germany in July 1917. Mustard gas is not a particularly effective killing agent but the skin of its victims got blistered, their eyes became very sore and they began to vomit. Mustard gas caused internal and external bleeding and attacked the bronchial tubes