Practice Test: General Science- 9 | Science & Technology for UPSC CSE

Question 1. ________metals pollutes the air of a city having large number of automobiles. 

Answer: Lead

Question 2. Nitrogen is utilised by the plant in the form of________ 

Answer: nitrate

Question 3. Pure water is obtained from sea water by the process of________ 

Answer: distillation

Question 4. Liquefied Petroleum Gas consists mainly of________ 

Answer: Methane, Butane and Propane

Question 5. German silver is an alloy of________ 

Answer: copper, zinc and nickel

Question 6. Antacids are found in medicines that cure________ 

Answer: stomachache

Question 7. The process of union of two or more molecules of a substance to form a large single molecule is called________ 

Answer: Polymerisation

Question 8. Iodine is administered to patients suffering from______ 

Answer: Goitre

Question 9. The combustible material on the tip of a safety match stick is________ 

Answer: Antimony sulphide

Question 10. The term ‘carat’ is used to express the purity of gold. The purest form of gold is________ 

Answer:  24 carats

Question 11. Some sources of energy are continuously produced in nature and are essentially inexhaustible. ________is such a source. 

Answer:  Geothermal power

Question 12. Ethyl alcohol from molasses, which is a by-product of the sugar industry, is made by the process called____ 

Answer: Fermentation

Question 13. Milk is a mixture of________ 

Answer: Carbohydrates, fats, proteins and water

Question 14. ________makes the water a very convenient medium for chemical reactions and biological process. 

Answer: It has a reasonably long temperature range between its freezing point and boiling point

Question 15. Alloys in which mercury is one of the metals, are called________ 

Answer: Amalgam

Question 16. Synthetic detergents are a mixture________ 

Answer: of sodium salts of aromatic and aliphatic sulphonic acids

Question 17. Detergents produce lather with hard water because________ 

Answer: the calcium and magnesium salts of sulphonic acids are soluble in water

Question 18. Lime water contains________ 

Answer: calcium hydroxide

Question 19. Cooking oil can be converted into vegetable ghee by the process of________ 

Answer: hydrogenation

Question 20. The weight of a rusted iron object is________that of an unrusted one. 

Answer: apreciably more than

Question 21. The acid present in lemons and oranges is________

Answer: citric acid

Question 22. Hardness of water is caused by soluble salts of_____ 

Answer: Calcium and Magnesium

Question 23. The purification of a substance which evaporates without melting can be carried out by________ 

Answer: Sublimation

Question 24. It is easier to compress substance in the gaseous state because the molecules in this state________

Answer: Have large space between them

Question 25. __is tungsten used in the manufcture of electric bulbs. 

Answer: It has high melting point

Question 26. Carbohydrates are composed of________ 

Answer: Carbon, hydrogen and oxygen

Question 27. Stainless steel is an alloy of________ 

Answer: Iron, c hromi um and nickel

Question 28. Whe milk is conv-erted into curd the sour taste is due to________ 

Answer: Acetic acid

Question 29. Water for civil sup-plies is commonly purified by____ 

Answer: chlorination

Question 30. During fermentation of sugar, the chief compound always for-med is________ 

Answer: ethyl alcohol

Question 31.‘Fixation of nitrogen’s implies________ 

Answer: the conversion of atmospheric nitrogen into useful compounds

Question 32. Wood Charcoal is commonly prepared by the process of burning wood________ 

Answer: out of contact with air

Question 33. The substance that is added to make natural rubber strong and more bouncy is________ 

Answer: sulphur

Question 34. Photographic plates are covered with black paper because________ 

Answer: the silv er bromide present on the plate is very sensitive to light and black paper prevents contact with light

Question 35. The pH of an aqueous solution of acetic acid is 2. It would increase on the addition of________ 

Answer: aqueous ammonia

Question 36. Commercially, the production of ammonia is important because it can be used in the________ 

Answer: production of fertilisers

Question 37. Pasteurization involves heating liquids or milks for___ 

Answer: 62°C for 30 minutes

Question 38. Teflon is a ________ 

Answer: Polymer

Question 39. The purest form of iron is________ 

Answer: Wrought iron

Question 40. Natural Rubber is a polymer of________ 

Answer: Isoprene

Question 41. Marsh gas consists of________ 

Answer: Methane

Question 42. Dry ice consists of________ 

Answer: Solid carbon dioxide

Question 43. A photographic plate uses________ 

Answer: Silver bromide

Question 44. In order to prevent the corrosion of iron pipes they are often coated with a layer of zinc. This process is termed________ 

Answer: galvanization

Question 45. The main chemical substance present in the bones and teeth of animal is________ 

Answer: calcium phosphate

Question 46. A catalyst is a substance which________ 

Answer: increases the speed of a reaction

Question 47. Heavy water________ 

Answer: contains deuterium in place of hydrogen

Question 48. PVC plastics are obtained from vinyl chloride by the process of________ 

Answer: polymerization

Question 49. Polythene is industrially prepared by the polymerization of ________ 

Answer: ethylene

Question 50. The metal generally mixed with gold while making ornament is______

Answer: copper