1) When a beam of white rays is dispersed by a prism which colour will be refracted to a larger extent?
Answer: Violet.
2) The modern atomic mass unit is based on __
Answer: Carbon-12.
3) What do you mean by photoelectric effect?
Answer: Emission of electrons by electromagnetic radiation striking on a metal surface.
4) A raincoat is made of what?
Answer: Polychloroethene.
5) What is the value of Planck’s constant in SI units?
Answer: 6.625 x 10’34 Is.
6) The total number of electrons present in 18 ml of water is __
Answer: 6.02 × 1024.
7) What is the velocity of light in m/s?
Answer: 3 x 108 m/s.
8) Which element on adding to natural rubber makes it less sticky in hot weather and less hard in cold weather?
Answer: Sulfur.
9) The scientist who introduced the model of the atom similar to the solar system?
Answer: Ernest Rutherford.
10) 3 g of a salt of molecular weight 30 is dissolved in 250 g of water. The molality of the solution is __
Answer: 0.4m.
11) What happens when an electron moves nearer to the nucleus of the atom?
Answer: Its energy decreases.
12) Which chemical causes Minamata disease?
Answer: Mercury.
13) What is molarity?
Answer: Number of moles of solute in one liter of the solution.
14) The weight of 1 × 1022 molecules of CuSO4 .5H2O is __
Answer: 4.14 g.
15) What kind of thermometer is used to determine the depression of freezing point?
Answer: Beckmann thermometer.
16) The absence of cobalt in minute quantities in human body causes what?
Answer: Pernicious anemia.
17) What do you mean by a buffer solution?
Answer: Solution which can maintain constant PH.
18) 27 g of Al will react completely with how many grams of oxygen?
(a) 8 g (b) 16 g (c) 32 g (d) 24 g
Answer: D.
19) Which element has no neutrons in it?
Answer: Hydrogen.
20) Which element can easily form chains?
Answer: Carbon.
21) What is the fundamental particle present in P – rays?
Answer: Electron.
22) A compound was found to contain nitrogen and oxygen in the ratio 28 gm and 80 gm respectively. The formula of the compound is
(a) NO (b) N2O3 (c) N2O5 (d) N2O4
Answer: C.
23) Give the name of the radioactive isotope of hydrogen:
Answer: Tritium.
24) Cement mixed with gravel, sand, and water is known as what?
Answer: Concrete.
25) What are isotopes?
Answer: Atoms having the same atomic number but a different mass number.
26) The largest number of molecules is in
(a) 36 g of water (b) 28 g of carbon monoxide (c) 46 g of ethyl alcohol (d) 54 g of nitrogen pentoxide
Answer: A.
27) What are isobars?
Answer: Same mass number but a different atomic number.
28) what’s the measure of overall performance of petrol in inner combustion engines?
Answer: Octane number.
29) What is Isotone?
Answer: Atoms having an equal number of neutrons.
30) The total number of electrons in one molecule of carbon dioxide is
(a) 22 (b) 44 (c) 66 (d) 88
Answer: A.
31) What do you mean by dating of objects?
Answer: Determination of age.
32) Glass is made out of what?
Answer: Sand.
33) Name any two nuclei used to make an atom bomb:
Answer: Uranium, Plutonium.
34) A gaseous mixture contains oxygen and nitrogen in the ratio of 1: 4 by weight. Therefore the ratio of their number of molecules is
(a) 1: 4 (b) 1: 8 (c) 7: 32 (d) 3: 16
Answer: C.
35) What is the half-life of 6C14?
Answer: 5760 years.
36) Which is considered to be an anomalous compound?
Answer: Water.
37) Bronze is an alloy of what?
Answer: Tin and copper.
38) 2.76 g of silver carbonate on being strongly heated yields a residue weighing
(a) 2.16 g (b) 2.48 g (c) 2.32 g (d) 2.64 g
Answer: A.
39) Which is the most widely used metal?
Answer: Iron.
40) How would you know that a chemical is pure or not?
Answer: By checking its melting point.
41) Which mineral is used making plaster and paper?
Answer: Gypsum.
42) M is the molecular weight of KMnO4. The equivalent weight of KMnO4 when it is converted into K2MnO4 is
(a) M (b) M/3 (c) M/5 (d) M/7
Answer: A.
43) Which is the metal as strong as steel but half as much in weight?
Answer: Titanium.
44) Which material is used in display devices, such as digital watches?
Answer: Liquid crystal.
45) Which metal is extracted by the Mond process?
Answer: Nickel.
46) If 0.50 mole of BaCl2 is mixed with 0.20 mol of Na3 PO4, the maximum number of moles of Ba3 (PO4) 2 that can be formed is
(a) 0.70 (b) 0.50 (c) 0.20 (d) 0.10
Answer: D.
47) Which is the most stable compound?
Answer: Sodium hydroxide.
48) Which chemical compound may soon be used as a fuel for driving vehicles?
Answer: Ethanol.
49) What is the purest form of iron?
Answer: Wrought iron.
50) One mole of N2H4 loses ten moles of electrons to form a new compound Y. Assuming that all the nitrogen appears in the new compound, what is the oxidation state of nitrogen in Y? (There is no change in the oxidation state of hydrogen).
(a) –1 (b) –3 (c) +3 (d) +5
Answer: C.
51) Which substance is received whilst magnesium is heated with lead oxide?
Answer: Mgo + Pb.
52) Which drug is present in cola drinks?
Answer: Caffeine.
53) What do you mean by horn silver?
Answer: Ore of silver, that is AgCl.
54) The oxidation number of carbon in CH2O is
(a) – 2 (b) + 2 (c) 0 (d) + 4
Answer: C.
55) Which mineral ores forms kidney-shaped crystals?
Answer: Haematite.
56) Which fuel produces the maximum heat per gram burnt?
Answer: Hydrogen.
57) Which mineral is often used as an abrasive?
Answer: Corundum.
58) A molal solution is one that contains one mole of a solute in:
(a) 1000 g of the solvent (b) one liter of the solvent (c) one liter of the solution (d) 22.4 liters of the solution
Answer: A.
59) What is an amalgam?
Answer: Mixture of metal and mercury.
60) Which element in the radioactive form is used for determining the age of artifacts, relics, bones, etc. of the past?
Answer: Carbon.
61) What is Pyrolusite?
Answer: Ore of manganese, Mn02.