Practice Questions

Q37.Product ' A ' of following sequence of reactions is (1) (2) (3) (4)

Q37. L-isomer of a compound ′A′(C4H8O4)gives a positive test with [Ag (NH3)2]+ . Treatment of ' A' with acetic anhydride yields triacetate derivative. Compound ' A' produces an optically active compound (B) and an optically inactive compound (C) on treatment with bromine water and HNO3 respectively. Compound (A) is : (1) (2) (3) (4)

Q38.The ( ∂T∂E )P of different types of half cells are as follows : A B C D 1 × 10−4 2 × 10−4 0. 1 × 10−4 0. 2 × 10−4 (Where E is the electromotive force). Which of the above half cells would be preferred to be used as reference electrode (1) A (2) B (3) C (4) D

Q38.Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R. Assertion A : [6] Annulene. [8] Annulene and cis −[10] Annulene, are respectively aromatic, not-aromatic and aromatic. ​ Reason R: Planarity is one of the requirements of aromatic systems. In the light of the above statements, choose the most appropriate answer from the options given below. (1) Both A and R are correct and R is the correct (2) Both A and R are correct but R is NOT the explanation of A . correct explanation of A . (3) A is correct but R is not correct. (4) A is not correct but R is correct.

Q38.In the given reaction sequence, the major product ' C' is : HNO3 Br2 alcoholic −−C8H10 → A → B → C H2 SO4 Δ KOH JEE Main 2022 (24 Jun Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)

Q38.Among the following marked proton of which compound shows lowest pKa value? (1) (2) (3) (4)

Q39.Which of the following reagents / reactions will convert ' A' to ' B'? (1) PCC oxidation (2) Ozonolysis (3) BH3, H2O2/ −OH followed by PCC oxidation (4) HBr, hydrolysis followed by oxidation by K2 Cr2 O7 .

Q40.The photochemical smog does not generally contain (1) NO (2) NO2 (3) SO2 (4) HCHO

Q40.The correct order of reduction potentials of the following pairs is A. Cl2 / Cl- B. I2 / I- C. Ag+ / Ag D. Na+ / Na E. Li+ / Li Choose the correct answer from the options given below. (1) A > B > C > E > D (2) A > C > B > E > D (3) A > B > C > D > E (4) A > C > B > D > E

Q40.Consider the following reaction : (1) Electrolysis 2 HSO−4 (aq) (2) Hydrolysis 2 HSO−4 + 2H+ + A The dihedral angle in product A in its solid phase at 110 K is (1) 104° (2) 111. 5° (3) 90. 2° (4) 111. 0°

Q43.Given below are two statements : JEE Main 2022 (28 Jun Shift 1) JEE Main Previous Year Paper Statement I: [Ni (CN)4]2− is square planar and diamagnetic complex, with dsp2 hybridization for Ni but [Ni (CO)4] is tetrahedral, paramagnetic and with sp3 hybridication for Ni. Statement II : [NiCl4]2− and [Ni (CO)4] both have same d-electron configuration, have same geometry and are paramagnetic. In light the above statements, choose the correct answer form the options given below (1) Both Statement I and Statement II are true. (2) Statement I is correct but statement II is false. (3) Statement I is incorrect but statement II is true. (4) Both Statement I and Statement II are false.

Q44.Arrange the following coordination compounds in the increasing order of magnetic moments. (Atomic numbers: Mn = 25; Fe = 26) A. [FeF6]3− B. [Fe (CN)6]3− C. [MnCl6]3− (high spin) D. [Mn (CN)6]3− Choose the correct answer from the options given below (1) A < B < D < C (2) B < D < C < A (3) A < C < D < B (4) B < D < A < C

Q45.Two isomers (A) and (B) with Molar mass 184 g/ mol and elemental compositio C, 52. 2%; H, 49% and Br 42. 9% gave benzoic acid and p− bromobenzoic acid, respectively on oxidation with KMnO4 . Isomer ′A′ is optically active and gives a pale yellow precipitate when warmed with alcoholic AgNO3 . Isomer ′A′ and ′B′ are, respectively : (1) (2) (3) (4) H3C −CHBr −C6H5 and and H3C −CHBr −C6H5

Q45.The reagent, from the following, which converts benzoic acid to benzaldehyde in one step is (1) LiAlH4 (2) KMnO4 (3) MnO (4) NaBH4

Q46.Isobutyraldehyde on reaction with formaldehyde and K2 CO3 gives compound ' A '. Compound ' A' reacts with KCN and yields compound ' B ', which on hydrolysis gives a stable compound ' C '. The compound ' C ' is (1) (2) (3) (4)

Q46.Decarboxylation of all six possible forms of diaminobenzoic acids C6H3(NH2)2 COOH yields three products A, B and C . Three acids give a product ' A ', two acids gives a product ' B ' and one acid give a product ' C '. The melting point of product ' C ' is (1) 63 °C (2) 90 °C (3) 104 °C (4) 142 °C

Q47.An organic compound 'A' on reaction with NH3 followed by heating gives compound B. Which on further strong heating gives compound C C8H5NO2. Compound C on sequential reaction with ethanolic KOH, alkyl chloride and hydrolysis with alkali gives a primary amine. The compound A is (1) (2) (3) (4)

Q47.An organic compound ' A ' contains nitrogen and chlorine. It dissolves readily in water to give a solution that turns litmus red. Titration of compound ' A ' with standard base indicates that the molecular weight of ' A ' is 131 ± 2 . When a sample of ' A ' is treated with aq. NaOH, a liquid separates which contains N but not Cl. Treatment of the obtained liquid with nitrous acid followed by phenol gives orange precipitate. The compound ' A ' is (1) (2) (3) (4)

Q50.When sugar ' X ' is boiled with dilute H2 SO4 in alcoholic solution, two isomers ' A' and ' B' are formed. ' A' on oxidation with HNO3 yields saccharic acid where as ' B' is laevorotatory. The compound ' X' is (1) Maltose (2) Sucrose (3) Lactose (4) Strach

Q52. PCl5 dissociates as PCl5(g) ⇌PCl3(g) + Cl2(g) 5 moles of PCl5 are placed in a 200 litre vessel which contains 2 moles of N2 and is maintained at 600 K. The equilibrium pressure is 2. 46 atm . The equilibrium constant Kp for the dissociation of PCl5 is___ ×10−3 . (nearest integer) (Given: R = 0. 082 L atm K−1 mol−1 ; Assume ideal gas behaviour)

Q53.for a real gas at 25 °C temperature and high pressure ( 99 bar) the value of compressibility factor is 2 , so the value of Van 1der Waal's constant ' b' should be_____ ×10−2 L mol−1 (Given R = 0. 083 L bar K−1 mol−1 )

Q54.Compound ' P' on nitration with dil. HNO3 yields two isomers (A) and (B). These isomers can be separated by steam distillations. Isomers (A) and (B) show the intramolecular and intermolecular hydrogen bonding respectively. Compound (P) on reaction with conc. HNO3 yields a yellow compound ' C', a strong acid. The number of oxygen atoms is present in compound ' C'

Q54.The major product ' A' of the following given reaction has sp2 hybridized carbon atoms. JEE Main 2022 (24 Jun Shift 1) JEE Main Previous Year Paper H+ 2, 7 -Dimethyl- 2, 6 -octadiene → A Major Product

Q55.In the estimation of bromine, 0. 5 g of an organic compound gave 0. 40 g of silver bromide. The percentage of bromine in the given compound is % (nearest integer) (Relative atomic masses of Ag and Br are 108u and 80u , respectively).

Q56.The cell potential for the given cell at 298 K Pt|H2(g, 1 bar)| H+(aq) Cu2+(aq) Cu(s) is 0. 31 V . The pH of the acidic solution is found to be 3, whereas the concentration of Cu2+ is 10x M. The value of x is _________. (Given: EΘ = 0. 34 V and 2.303F RT = 0. 06 V ) Cu2+ / Cu JEE Main 2022 (29 Jun Shift 2) JEE Main Previous Year Paper