Practice Questions

Q42.Which of the following is a Lewis acid? (1) PH3 (2) NF3 (3) NaH (4) B(CH3)3

Q43.Two compounds I and II are eluted by column chromato-graphy(adsorption of I > II). Which one of the following is a correct statement? (1) II moves slower and has higher Rf value than I (2) II moves faster and has higher Rf value than I (3) I moves faster and has higher Rf value than II (4) I moves slower and has higher Rf value than I

Q45.The IUPAC name of the following compound is (1) 3−ethyl −4−methylhex −4−ene (2) 4, 4−diethyl −3−methylbut −2−ene (3) 4−methyl −3−ethylhex −4−ene (4) 4−ethyl −3−methylhex −2−ene

Q45.The trans-alkenes are formed by the reduction of alkynes with (1) Sn −HCl (2) H2 −Pd /C, BaSO4 (3) NaBH4 (4) Na / liq. NH3

Q46.Which one of the following is not a property of physical adsorption? (1) Higher the pressure, more the adsorption (2) Greater the surface area, more the adsorption (3) Lower the temperature, more the adsorption (4) Unilayer adsorption occurs

Q46.The recommended concentration of fluoride ion in drinking water is up to 1 ppm as fluoride ion is required to make teeth enamel harder by converting [3 Ca3 (PO4)2. Ca (OH)2] to: (1) [3 Ca (OH)2. CaF2] (2) [CaF2] (3) [3(CaF2). Ca (OH)2] (4) [3 Ca3 (PO4)2. CaF2]

Q46.Biochemical oxygen demand(BOD) value can be a measure of water pollution caused by the organic matter. Which of the following statements is correct? (1) Polluted water has BOD value higher than (2) Aerobic bacteria decreases the BOD value 10ppm (3) Anaerobic bacteria increases the BOD value (4) Clean water has BOD value higher than 10 ppm

Q47.Which of the following arrangements shows the schematic alignment of magnetic moments of antiferromagnetic substance? (1) (2) (3) (4)

Q47.Which type of 'defect' has the presence of cations in the interstitial sites? (1) Metal deficiency defect (2) Schottky defect (3) Vacancy defect (4) Frenkel defect

Q50.Which of the following arrangements shows the schematic alignment of magnetic moments of antiferromagnetic substance? (1) (2) (3) (4)

Q57.The main reduction product of the following compound with NaBH4 in methanol is: (1) (2) (3) (4)

Q58.The copolymer formed by addition polymerization of styrene and acrylonitrile in the presence of peroxide is: (1) (2) (3) (4)

Q58.The copolymer formed by addition polymerization of styrene and acrylonitrile in the presence of peroxide is JEE Main 2018 (15 Apr) JEE Main Previous Year Paper (1) (2) (3) (4)

Q59.Glucose on prolonged heating with HI gives (1) 6−iodohexanal (2) n−Hexane (3) 1−Hexene (4) Hexanoic acid

Q60.Which of the following is the correct structure of adenosine ? JEE Main 2018 (15 Apr Shift 1 Online) JEE Main Previous Year Paper (1) (2) (3) (4)

Q60.Which of the following is the correct structure of adenosine? (1) (2) (3) (4) JEE Main 2018 (15 Apr) JEE Main Previous Year Paper

Q33.Among the following species which option contains all isoelectronic species? (1) 𝑂-, 𝐹-, 𝑁𝑎, 𝑀𝑔+ (2) 𝑂2 - , 𝐹-, 𝑁𝑎, 𝑀𝑔2 + (3) 𝑂-, 𝐹-, 𝑁𝑎+, 𝑀𝑔2 + (4) 𝑂2 - , 𝐹-, 𝑁𝑎+, 𝑀𝑔2 +

Q40.The following reaction occurs in the Blast Furnace where iron ore is reduced to iron metal: Fe2O3(s) + 3CO(g) ⇌2Fe (l) + 3CO2(g) Using the Le Chatelier's principle, predict which one of the following will not disturb the equilibrium? (1) Addition of CO2 (2) Removal of CO2 (3) Addition of Fe2O3 (4) Removal of CO Q41. 50 mL of 0 .2 M ammonia solution is treated with 25 mL of 0. 2 M HCl. If pKb of ammonia solution is 4. 75, the pH of the mixture will be: (1) 8. 25 (2) 9. 25 (3) 3. 75 (4) 4. 75

Q42.A water sample has ppm level concentration of following anions F- = 10; SO42 - = 100; NO3- = 50 The anion/anions that make/makes the water sample unsuitable for drinking is/are (1) Both SO42 - and NO3- (2) Only F- (3) Only SO42 - (4) Only NO3-

Q43.A metal crystallizes in a face centred cubic structure. If the edge length of its unit cell is 'a', the closest approach between two atoms in the metallic crystal will be (1) 2√2a (2) √2a a (3) (4) 2a √2

Q44.The IUPAC name of the following compound is: (1) 2−Ethyl −1, 1−dimethyl cyclohexane (2) 1, 1−Dimethyl −2−ethyl cyclohexane (3) 2, 2−Dimethyl −1 −1−ethyl cyclohexane (4) 1−Ethyl −2, 2−dimethyl cyclohexane

Q45.Given = - 0 .74 V ECl2o / Cl- = 1 .36 V, ECr3o + / Cr o ECr2O72 - / Cr3 + = 1 .33 V, EMnO4o - / Mn2 + = 1 .51 V . Among the following, the strongest reducing agent is: JEE Main 2017 (02 Apr) JEE Main Previous Year Paper (1) Mn2 + (2) Cr3 + (3) Cl- (4) Cr

Q46.Identify the pollutant gases largely responsible for the discoloured and lustreless nature of marble of the Taj Mahal. (1) SO2 and O3 (2) O3 and CO2 (3) SO2 and NO2 (4) CO2 and NO2 JEE Main 2017 (08 Apr Online) JEE Main Previous Year Paper Q47. 5g of Na2 SO4 was dissolved in x g of H2O . The change in freezing point was found to be 3 .82o C . If Na2 SO4 is 81. 5% ionised, the value of x ( Kf for water = 1 .86o C kg mol−1 ) is approximately: (molar mass of S = 32 g mol−1 and that of Na = 23 g mol−1 ) (1) 25 g (2) 65 g (3) 15 g (4) 45 g

Q47.The Tyndall effect is observed only when the following conditions are satisfied, i The diameter of the dispersed particles is much smaller than the wavelength of the light used. ii The diameter of the dispersed particle is not much smaller than the wavelength of the light used. iii The refractive indices of the dispersed phase and dispersion medium are almost similar in magnitude. iv The refractive indices of the dispersed phase and dispersion medium differ greatly in magnitude. (1) ii and iv (2) i and iii (3) ii and iii (4) i and iv

Q51.Adsorption of gas on a surface follows Freundlich adsorption isotherm. The plot of log mx versus log(P) gives a straight line with slope equal to 0. 5 , then: ( x is the mass of the gas adsorbed per gram of adsorbent) m (1) adsorption is proportional to the square root of (2) adsorption is proportional to the square of pressure. pressure. (3) adsorption is proportional to the pressure. (4) adsorption is independent of pressure.