Practice Questions

Q47.A solution is prepared by mixing 8. 5 g of CH2 Cl2 and 11.95 g of CHCl3 . If vapour pressure of CH2 Cl2 and CHCl3 at 298 K are 415 and 200 mm Hg respectively, the mole fraction of CHCl3 in vapour form is: (Molar mass of Cl = 35.5 g mol−1) (1) 0. 162 (2) 0. 675 (3) 0. 325 (4) 0. 486 JEE Main 2017 (09 Apr Online) JEE Main Previous Year Paper

Q48.The products obtained when chlorine gas reacts with cold and dilute aqueous NaOH are (1) ClO2- and ClO3- (2) Cl- and ClO- (3) Cl- and ClO2- (4) ClO- and ClO3-

Q48.Consider the following standard electrode potentials ( Eo in volts) in aqueous solution: Element M3+/M M+/M Al −1.66 +0.55 Tl +1.26 −0.34 Based on these data, which of the following statements is correct? (1) Tl+ is more stable than Al3+ (2) Al+ is more stable than Al3+ (3) Tl3+ is more stable than Al3+ (4) Tl+ is more stable than Al+

Q48.Which of the following ions does not liberate hydrogen gas on reaction with dilute acids? (1) V2+ (2) Ti2+ (3) Mn2+ (4) Cr2+

Q49.What is the standard reduction potential (Eo) for Fe3+ →Fe? Given that: Fe2+ + 2e−→Fe; Eo = −0 .47 V Fe2+ / Fe Fe3+ + e−→Fe2+; Eo = +0 .77 V Fe3+ / Fe2+ (1) −0 .057 V (2) +0 .30 V (3) −0 .30 V (4) +0 .057 V

Q49.Which of the following reactions is an example of a redox reaction? (1) XeF2 + PF5 →XeF+PF6- (2) XeF6 + H2O →XeOF4 + 2HF (3) XeF6 + 2H2O →XeO2F2 + 4HF (4) XeF4 + O2F2 →XeF6 + O2

Q49.To find the standard potential of M3+/M electrode, the following cell is constituted: Pt /M/M3+ (0 .001 mol L−1)/ Ag+ (0 .01 mol L−1)/ Ag The emf of the cell is found to be 0. 421 volt at 298 K. The standard potential of half-reaction M3+ + 3e−→M at 298 K will be: (Given: E⊝ at 298 K = 0. 80 volt) Ag+/Ag (1) 0. 38 volt (2) 1. 28 volt (3) 0. 32 volt (4) 0. 66 volt

Q50.The rate of a reaction quadruples when the temperature changes from 300 to 310 K . The activation energy of this reaction is: (Assume Activation energy and pre-exponential factor are independent of temperature; ln(2) = 0. 693; R = 8. 314 J mol−1 K−1 ) (1) 53. 6 kJ mol−1 (2) 214. 4 kJ mol−1 (3) 107. 2 kJ mol−1 (4) 53. 7 kJ mol−1

Q50.In the following reactions, ZnO is respectively acting as a/an, (i) ZnO + Na2O →Na2ZnO2 (ii) ZnO + CO2 →ZnCO3 (1) base and base. (2) acid and acid. (3) acid and base. (4) base and acid.

Q50.The rate of a reaction A doubles on increasing the temperature from 300 to 310 K . By how much, the temperature of reaction B should be increased from 300 K so that rate doubles if activation energy of the reaction B is twice to that of reaction A. (1) 4. 92 K (2) 9. 84 K (3) 19. 67 K (4) 2. 45 K

Q51.The sodium salt of an organic acid X produces effervescence with concentrated H2SO4. X reacts with the acidified aqueous CaCl2 solution to give a white precipitate which decolourises acidic solution of KMnO4. X is (1) HCOONa (2) CH3COONa (3) Na2C2O4 (4) C6H5COONa

Q51.Among the following, the correct statement is: (1) sols of metal sulphides are lyophilic. (2) Brownian movement is more pronounced for smaller particles than for bigger-particles. (3) one would expect charcoal to adsorb chlorine (4) Hardy Schulze law states that bigger the size of more than hydrogen sulphide. the ions, the greater is its coagulating power.

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.

Q52.On treatment of 100 mL of 0 . 1 M solution of CoCl3 . 6H2O with excess AgNO3; 1 .2 × 1022 ions are precipitated. The complex is: (1) CoH2O3Cl3 . 3H2O (2) CoH2O6Cl3 (3) CoH2O5ClCl2 . H2O (4) CoH2O4Cl2Cl . 2H2O JEE Main 2017 (02 Apr) JEE Main Previous Year Paper

Q52.The number of S = O and S −OH bonds present in peroxodisulphuric acid and pyrosulphuric acid respectively are: (1) (2 and 2) and (2 and 4). (2) (4 and 2) and (4 and 2). (3) (4 and 2) and (2 and 4). (4) (2 and 2) and (2 and 2).

Q52.The number of P −OH bonds and the oxidation state of phosphorus atom in pyrophosphoric acid (H4P2O7), respectively are: (1) Five and four. (2) Four and five. (3) Five and five. (4) Four and four.

Q53.A solution containing a period −IV cation gives a precipitate on passing H2S. A solution of this precipitate in dil. HCl produces a white precipitate with NaOH solution and bluish-white precipitate with basic potassium ferrocyanide. The cation is (1) Mn2+ (2) Zn2+ (3) Ni2+ (4) CO2+ JEE Main 2017 (08 Apr Online) JEE Main Previous Year Paper

Q53.The correct sequence of decreasing number of π -bonds in the structure of H2SO3, H2SO4 and H2S2O7 is: (1) H2S2O7 > H2SO3 > H2SO4 (2) H2S2O7 > H2SO4 > H2SO3 (3) H2SO4 > H2S2O7 > H2SO3 (4) H2SO3 > H2SO4 > H2S2O7

Q53.The major product obtained in the following reaction is, (1) C6H5CH = CHC6H5 (2) + C6H5CHOtBuCH2C6H5 (3) - C6H5CHOtBuCH2C6H5 (4) ± C6H5CHOtBuCH2C6H5

Q54.The major product of the following reaction is: (1) CH3 CH = CH −CH = CHCH3 (2) CH2 = CHCH = CHCH2 CH3 (3) CH3 CH = C = CHCH2 CH3 (4) CH2 = CHCH2 CH = CHCH3

Q54. XeF6 on partial hydrolysis with water, produces a compound X. The same compound X is formed when XeF6 reacts with silica. The compound X is: (1) XeF4 (2) XeF2 (3) XeO3 (4) XeOF4 Q55. [Co2 (CO)8] displays (1) no Co −Co bonds, six terminal CO and two (2) no Co −Co bonds, four terminal CO and four bridging CO. bridging CO. (3) one Co −Co bonds, six terminal CO and two (4) one Co −Co bonds, four terminal CO and four bridging CO. bridging CO.

Q54.The increasing order of the reactivity of the following halides for the SN1 reaction is (1) ( II ) < ( I ) < ( III ) (2) ( I ) < ( III ) < ( II ) (3) ( II ) < ( III ) < ( I ) (4) ( III ) < ( II ) < ( I ) Q55.3 - Methyl - pent-2 - ene on reaction with HBr in presence of peroxide forms an addition product. The number of possible stereoisomers for the product is (1) zero (2) two (3) four (4) six

Q56.In the following reaction sequence: JEE Main 2017 (09 Apr Online) JEE Main Previous Year Paper Compound I is (1) (2) (3) (4)

Q56.The major product of the following reaction is: (1) (2) (3) (4) JEE Main 2017 (08 Apr Online) JEE Main Previous Year Paper

Q56.Which of the following, upon treatment with tert-BuONa followed by addition of bromine water, fails to decolourize the colour of bromine? (1) (2) (3) (4)