Practice Questions

Q42.A solution containing 62 g ethylene glycol in 250 g water is cooled to −10oC . If Kf for water is 1.86 K kg mol−1 , the amount of water (in g ) separated as ice is: (1) 48 (2) 64 (3) 16 (4) 32

Q42.The correct order for acid strength of compounds CH ≡CH, CH3 −C ≡CH and CH2 = CH2 is as follows: (1) CH3 −C ≡CH > CH ≡CH > CH2 = CH2 (2) HC ≡CH > CH3 −C ≡CH > CH2 = CH2 (3) CH ≡CH > CH2 = CH2 > CH3 −C ≡CH (4) CH2 −C ≡CH > CH2 = CH2 > HC ≡CH JEE Main 2019 (12 Jan Shift 1) JEE Main Previous Year Paper

Q42.The increasing order of the reactivity of the following compounds towards electrophilic aromatic substitution reactions is: JEE Main 2019 (10 Apr Shift 1) JEE Main Previous Year Paper (1) II < I < III (2) III < II < I (3) III < I < II (4) I < III < II

Q42.In chromatography, which of the following statements is incorrect for Rf? (1) Higher Rf value means higher adsorption. (2) The value of Rf cannot be more than one. (3) Rf value depends on the type of chromatography. (4) Rf value of dependent on the mobile phase.

Q43.The major product (s) obtained in the following reaction is/are: (1) (2) (3) (4)

Q43.The elevation in boiling point for 1 molal solution of glucose is 2 K. The depression in freezing point for 2 molal solution of glucose in the same solvent is 2 K. The relation between Kb and Kf is: (1) Kb = 2 Kf (2) Kb = 1 .5 Kf (3) Kb = Kf (4) Kb = 0 .5 Kf

Q43.The maximum prescribed concentration of copper in drinking water is: JEE Main 2019 (08 Apr Shift 2) JEE Main Previous Year Paper (1) 3 ppm (2) 5 ppm (3) 0.5 ppm (4) 0.05 ppm

Q43.If the standard electrode potential for a cell is 2 V at 300 K, the equilibrium constant (K) for the reaction. Zn(s) + Cu2+(aq) ⇌Zn2+(aq) + Cu(s) at 300 K is approximately: (R = 8 JK −1mol−1, F = 96000 C mol−1) (1) e−160 (2) e−80 (3) e160 (4) e320

Q43.Which of these factors does not govern the stability of a conformation in acyclic compounds? (1) Steric interactions (2) Angle strain (3) Torsional strain (4) Electrostatic forces of interaction

Q43.The compounds A and B in the following reaction are, respectively: (1) 𝐴= Benzyl alcohol, 𝐵= Benzyl isocyanide (2) 𝐴= Benzyl chloride, 𝐵= Benzyl isocyanide (3) 𝐴= Benzyl alcohol, 𝐵= Benzyl cyanide (4) 𝐴= Benzyl chloride, 𝐵= Benzyl cyanide

Q43.The higher concentration of which gas in air can cause stiffnes of flower buds? (1) NO (2) CO2 (3) SO. (4) CO

Q43.Heating of 2-chloro-1-phenylbutane with EtOK/EtOH gives X as the major product. Reaction X with Hg(OAc)2/H2O followed by NaBH4 gives Y as the major product. Y is: (1) (2) (3) (4)

Q43.The regions of the atmosphere, where clouds form and where we live, respectively, are: (1) Troposphere and Troposphere (2) Stratosphere and Stratosphere (3) Stratosphere and Troposphere (4) Troposphere and Stratosphere

Q43.Consider the given plot of enthalpy of the following reaction between A and B. A + B →C + D. Identify the incorrect statement. JEE Main 2019 (09 Apr Shift 2) JEE Main Previous Year Paper (1) Formation of A and B from C has highest enthalpy of activation. (2) D is kinetically stable product. (3) C is the thermodynamically stable product. (4) Activation enthalpy to form C is 5 kJ mol−1 less than that to form D. Q44. 10 mL of 1 mM surfactant solution forms a monolayer covering 0.24 cm2 on a polar substrate. If the polar head is approximated as a cube, what is its edge length? (1) 1.0 pm (2) 0.1 nm (3) 2.0 pm (4) 2.0 nm

Q43.The compound that is NOT a common component of photochemical smog is: (1) O3 (2) CF2Cl2 (3) (4) CH2 = CHCHO

Q43.Peroxyacetyl nitrate (PAN), an eye irritant, is produced by: (1) Classical smog (2) Acid rain (3) Organic waste (4) Photochemical smog

Q43.Excessive release of CO2 into the atmosphere results in (1) global warming. (2) polar vortex. (3) depletion of ozone. (4) formation of smog.

Q43.The major product of the following reaction is: (1) (2) (3) (4)

Q44.The major product of the following addition reaction is (1) (2) (3) (4) JEE Main 2019 (12 Apr Shift 1) JEE Main Previous Year Paper

Q44.Consider the bcc unit cells of the solids 1 and 2 with the position of atoms as shown below. The radius of atom B is twice that of atom A . The unit cell edge length is 50 % more in solid 2 than in 1 . What is the approximate packing efficiency in solid 2 ? (1) 90 % (2) 45 % (3) 75 % (4) 65 %

Q44.For the reaction, 2A + B → products, when the concentration of A and B both were doubled, the rate of the reaction increased from 0.3 mol L−1s−1 to 2.4 mol L−1s−1. When the concentration of A alone is doubled, the rate increased from 0.3 mol L−1s−1 to 0.6 mol L−1s−1. Which one of the following statements is correct? (1) Order of the reaction with respect to B is 2 (2) Total order of the reaction is 4 (3) Order of the reaction with respect to A is 2 (4) Order of the reaction with respect to B is 1

Q44.In the cell, Pt(s)|H2(g, 1 bar)| HCl (aq)|AgCl(s)| Ag(s)|Pt(s),the cell potential is 0 .92 V when a 10−6 molar HCl solution is used. The standard electrode potential of Ag AgCl Cl− electrode is: (Given, 2.303RT F = 0 .06 V at 298 K) (1) 0 .76 V (2) 0 .20 V (3) 0 .40 V (4) 0 .94 V

Q44.The radius of the largest sphere which fits properly at the centre of the edge of a body centred cubic unit cell is : (Edge length is represented by 'a') (1) 0.027 a (2) 0.047 a (3) 0.134a (4) 0.067 a

Q44.The primary pollutant that leads to photochemical smog is: (1) nitrogen oxides (2) ozone (3) acrolein (4) Sulphur dioxide

Q44.The major product obtained in the given reaction is: (1) (2) (3) (4)