1. The blue complex formed on addition of conc. NH4OHsolution to a Cu2+ salt solution has the s tructure?(a) [Cu(NH4)4]2+ (b) [Cu(NH3)2]2+(c) [Cu(NH3)4]2+ (d) [Cu(NH4)2]2+2. Sodium thiosulphate is used in photography to(a) Reduce silver bromide to silver(b) Convert metallic silver to silver salt(c) Remove and decompose AgBr as a soluble silverthiosulphate complex(d) Remove reduce silver3. The black compound formed during the reaction betweensodium thiosulphate and silver nitrate is(a) Silver thiosulphate (Ag2S2O3)(b) Silver sulphide (Ag2S)(c) Sliver sulphate (Ag2SO4)(d) Silver sulphite (Ag2SO3)4. Parke’s process is used(a) To extract Ag using NaCN(b) To extract Cu using CuFeS2(c) To extract Ag from argentiferrous lead(d) To extract Ag by forming amalgam5. The lanthanides contraction is responsible for the fact that(a) Zr and Y have about the same radius(b) Zr and Nb have similar oxidation state(c) Zr and Hf have about the same radius(d) Zr and Zn have the same oxidation state6. Which of the following element is responsible for oxidation ofwater of O2 in biological process?(a) Fe (b) Mn(c) Cu (d) Mo7. In order to prepare one litre normal solution of KMNO4, howmany grams of KMNO4 are required if the solution is to beused in acidic medium for oxidation?(a) 158 g (b) 62.0 g(c) 31.6 g (d) 790 g8. The alloy best suited for making metre scales is(a) Stainless steel (b) Invar(c) Alnico (d) Tungsten steel9. Molecular formula of corrosive sublimate is(b) H (b) Hg2Cl2(d) HgS (d) HgCl10. Wrought iron :(a) Pure iron with 0.1 to 0.2% C(b) Pig iron(c) An alloy of steel(d) Impure sulphide ore iron11. In the manufacture of iron from haematite, limestone isadded to act as :(a) Flux (b) Slag(c) A reducing agent (d) An oxidizing agent12. An extremely hot copper wire reacts with steam to give(a) CuO (b) Cu2O(c) Cu2O2 (d) CuO213. Copper displaces which of the metal from their salt solution?(a) AgNO3 (b) ZnSO4(c) FeSO4 (d) All of these14. The colour of FeSO4.(NH4)2SO4.6H2O is(a) Red (b) White(c) Blue (d) Green15. A white solid halide of mercury forms a black mixtureNH4OH. The halide is(a) HgCl2 (b) HgCl2(c) Hg2Cl2 (d) Hg2Cl216. Spelter is(a) Impure Cu (b) Impure Zn(c) ZnO (d) CuO17. 18 carat gold contains(a) 18% Gold (b) 24% Gold(c) 75% Gold (d) 60% Gold18. Colourless solutions of the following four salts are palcedseparately in four different test tubes and a strip of copper isdipped in each one these. Which solution will turn blue?(a) KNO3 (b) AgNO3(c) Zn(NO3)2 (d) ZnSO419. Which of the following is used in the preparation of chlorine?(a) Only MnO2 (b) Only KMnO4(c) Both MnO2 and KMnO4 (d) Either MnO2 or KMnO4

Kala David , 12 Years ago

Grade 12