Practice Questions

Q50.The photoelectric current from Na (work function, w0 = 2. 3 eV ) is stopped by the output voltage of the cell Pt(s)∥H2(g, 1 bar)| HCl(aq⋅, pH = 1)| AgCl(s) ∣Ag(s) the pH of aq. HCl required to stop the photoelectric current from K(w0 = 2. 25 eV), all other conditions remaining the same, is … … … . ×10−2 (to the nearest integer). Given 2. 303 RTF = 0. 06V; E0AgCl / Ag /Cl = 0. 22V

Q50.Complexes (ML5) of metals Ni and Fe have ideal square pyramidal and trigonal bipyramidal geometries, respectively. The sum of the 90o, 120o and 180o L −M −L angles in the two complexes is_______

Q35.The entropy change associated with the conversion of 1 kg of ice at 273 K to water vapours at 383 K is: (Specific heat of water liquid and water vapour are 4.2 kJ K − and 2.0 kJ K −1kg−1 ; heat of liquid fusion and vaporization of water are 334 kJ kg−1 and 2491 kJ kg−1 , respectively). ( log 273 = 2.436, log 373 = 2.572, log 383 = 2.583 ) (1) 9.26 kJ kg−1K −1 (2) 2.64 kJ kg−1K −1 (3) 8.49 kJ kg−1K −1 (4) 7.90 kJ kg−1K −1

Q36.The molar solubility of Cd(OH)2 is 1.84 × 10−5M in water. The expectes solunility of Cd(OH)2 in a buffer solution of pH = 12 is: (1) 2.49 × 10−10M (2) 2.491.84 × 10−9M (3) 1.84 × 10−9M (4) 6.23 × 10−11M

Q36.A mixture of 100 m mol of Ca (OH)2 and 2 g of sodium sulphate was dissolved in water and the volume was made up to 100 mL. What is the mass of calcium sulphate formed and the concentration of OH− in resulting solution, respectively? (Molar mass of Ca (OH)2, Na2 SO4 and CaSO4 are 74, 143 and 136 g mol−1, respectively; Ksp of Ca (OH)2 is 5 .5 ×10−6 ) (1) 1 .9 g, 0 .14 mol L−1 (2) 13 .6 g, 0 .28 mol L−1 (3) 1 .9 g, 0 .28 mol L−1 (4) 13 .6 g, 0 .14 mol L−1

Q36.In order to oxidize a mixture of one mole of each of FeC2O4, Fe2 ( C2O4 ) 3, FeSO4 and Fe2 ( SO4 ) 3 in acidic medium, the number of moles of KMnO4 is: (1) 1 (2) 2 (3) 3 (4) 1.5

Q37.Consider the following statements (a) The pH of a mixture containing 400 mL of 0.1 M H2SO4 and 400 mL of 0.1 M NaOH will be approximately 1.3. (b) Ionic product of water is temperature dependent. (c) A monobasic acid with Ka = 10−5 has a pH = 5 . The degree of dissociation of this acid is 50% . (d) The Le Chatelier's principle is not applicable to common-ion effect. The correct statements are: (1) (b) and (c) (2) (a), (b) and (d) (3) (a) and (b) (4) (a), (b) and (c)

Q37.Two solids dissociate as follows: A (s) ⇌B (g) + C (g); KP1 = x atm2 D (s) ⇌C (g) + E (g); KP2 = y atm2 The total pressure when both the solids dissociate simultaneously is: (1) √x + y atm (2) x2 + y2 atm (3) (x + y) atm (4) 2(√x + y) atm Q38. 50 mL of 0 .5 M oxalic acid is needed to neutralize 25 mL of sodium hydroxide solution. What is the amount of NaOH in 50 mL of the given sodium hydroxide solution? (1) 2 g (2) 4 g (3) 1 g (4) 8 g

Q42.Which one of the following alkenes when treated with HCl yields majorly an anti Markovnikov product? (1) CH3O - CH = CH2 (2) Cl - CH = CH2 (3) H2N - CH = CH2 (4) F3C - CH = CH2

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.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

Q45.Molecules of benzoic acid (C6H5 COOH) dimerise in 30 g of benzene. ' w ' g of benzoic acid shows a depression in freezing point equal to 2 K. If the percentage association of the acid to form dimer in the solution is 80, then w is: ( Given that Kf = 5 Kmol−1 , molar mass of benzoic acid = 122 gmol−1) (1) 1.0g (2) 2.4g (3) 1.8g (4) 1.5g Q46. ∧om for NaCl, HCl and NaA are 126.4, 425.9 and 100 .5 S cm2 mol−1 respectively. If the conductivity of 0 .001 M HA is 5 × 10−5S cm−1 , degree of dissociation of HA is (1) 0.125 (2) 0.75 (3) 0.25 (4) 0.50

Q52.The correct order of the spin –only magnetic moment of metal ions in the following low-spin complexes, 4 - 4 - 3 + 2 + [V ( CN ) 6] , [Fe ( CN ) 6] , [Ru ( NH3 ) 6] and [Cr ( NH3 ) 6] , is: (1) V2 + > Cr2 + > Ru3 +(2)>Cr2Fe2++ > V2 + > Ru3 +(3)> Cr2Fe2++ > Ru3 + > Fe2 +(4)> V2V2++ > Ru3 + > Cr2 + > Fe2 + JEE Main 2019 (08 Apr Shift 1) JEE Main Previous Year Paper

Q53.The complex ion that will lose its crystal field stabilization energy upon oxidation of metal to +3 state is: (1) Niphen3 2 + (2) Fephen3 2 + (3) Cophen3 2 + (4) Znphen3 2 +

Q53.The total number of isomers for a square planar complex: [MCl(F)(NO2)(SCN)] is: (1) 12 (2) 16 (3) 4 (4) 8

Q53.The major product in the following conversion is JEE Main 2019 (12 Jan Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)

Q55.The major product of the following reaction is: JEE Main 2019 (10 Apr Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)

Q56. In the following compound, the favourable site/s for protonation is/are : JEE Main 2019 (11 Jan Shift 2) JEE Main Previous Year Paper (1) (a) and (e) (2) (b), (c) and (d) (3) (a) and (d) (4) (a)

Q58.With dehydrating agent present which dicarboxylic acid is least reactive towards forming an anhydride? JEE Main 2019 (10 Jan Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)

Q59.The correct match between column-I and column-II is Column-I (drug) Column-II (test) (A) Chloroxylenol (P) Carbylamine test (B) Norethindrone (Q) Sodium hydrogen carbonate test (C) Sulphapyridine (R) Ferric chloride test (D) Penicillin (S) Baeyer’s test (1) A →R, B →P, C →S, D →Q (2) A →Q, B →S, C →P, D →R (3) A →Q, B →P, C →S, D →R (4) A →R, B →S, C →P, D →Q

Q60.The increasing order of pKa of the following amino acids in aqueous solution is Glycine, Aspartate, Lysine, Arginine. (1) Arginine < Lysine < Glycine < Aspartate (2) Aspartate < Glycine < Arginine < Lysine (3) Glycine < Aspartate < Arginine < Lysine (4) Aspartate < Glycine < Lysine < Arginine

Q60.The correct structure of the product ‘P’ in the following reaction is NEt3 −Asn −Ser + (CH3 CO)2O → P (excess) JEE Main 2019 (10 Jan Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)

Q37.At 320 K, a gas A2 is 20 % dissociated to A(g) . The standard Gibbs free energy change at 320 K and 1 atm in J mol–1 is approximately: (R = 8 .314 JK–1 mol–1 ; ln 2 = 0 .693 ; ln 3 = 1 .098) (1) 1844 (2) 2068 (3) 4281 (4) 4763

Q44.When 9.65 ampere current was passed for 1.0 hour into nitrobenzene in acidic medium, the amount of p- aminophenol produced is: (1) 109.0 g (2) 98.1 g (3) 9.81 g (4) 10.9 g

Q45.The correct match between items of List-I and List-II is : (1) (A)-(r),(B)-(s), (C)-(p),(D)-(q) (2) (A)-(p),(B)-(s), (C)-(r),(D)-(q) (3) (A)-(r), (B)-(p), (C)-(q), (D)-(s) (4) (A)-(r),(B)-(p), (C)-(s),(D)-(q)