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1. The chemical formula of lead, sulphate is, , (a) Pb2SO,4, (b) Pb(SOa)2, (c) PbSO,, (d) Pb2(SOx)s, , 2. Which information is not conveyed, by a balanced chemical equation?, , (a) Physical states of reactants, and products, , (b) Symbols and formulae of all, the substances involved in a, particular reaction, , (c) Number of atoms/molecules, of the reactants and products formed, , (d) Whether a particular reaction is, actually feasible or not
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3. Chemically rust is, (a) hydrated ferrous oxide, , (b) only ferric oxide, , (c) hydrated ferric oxide, , (d) none of these, , 4. Both CO2 and H2 gases are, (a) heavier than air, , (b) colourless, , (c) acidic in nature, , (d) soluble in water, , 5. Which of the following gases can, be used for storage of fresh sampel, of an oil for a long time?, , (a) Carbon dioxide or oxygen, (b) Nitrogen or helium, (c) Helium or oxygen
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(d) Nitrogen or oxygen, , 6. The electrolytic decomposition of, water gives Hz and Oz in the ratio of, , (a) 1:2 by volume, (b) 2:1 by volume, (c) 8:1 by mass, (d) 1:2 by mass, , 7. Inthe decomposition of lead (Il), nitrate to give lead (II) oxide, nitrogen, dioxide and oxygen gas, the, coefficient of nitrogen dioxide (in the, balanced equation) is, , (a) 1, (b) 2, (c) 3, (d) 4
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8. Fatty foods become rancid due to, the process of, , (a) oxidation, (b) corrosion, (c) reduction, (d) hydrogenation, , 9. We store silver chloride in a dark, coloured bottle because it is, , (a) a white solid, (b) undergoes redoc reaction, (c) to avoid action by sunlight, (d) none of the above, , 10. Silver article turns black when, kept in the open for a few days due to, formation of, , (a) H2S
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(b) Ags, (c) AgSO., (d) Ag2S, , 11. When crystals of lead nitrate are, heated strongly in a dry test tube, , (a) crystals immediately melt, (b) a brown residue is left, , (c) white fumes appear in the tube, (d) a yellow residue is left, , 12. Dilute hydrochloric acid is added, to granulated zinc taken in a test, tube. The following observations are, recorded. Point out the correct, observation., , (a) The surface of metal becomes, shining
