Practice Questions

Q35.One mole of an ideal monoatomic gas is subjected to changes as shown in the graph. The magnitude of the work done (by the system or on the system) is _______ J (nearest integer) Given : log 2 = 0.3, ln 10 = 2.3

Q35.Gibbs energy vs T plot for the formation of oxides is given below. For the given diagram, the correct statement is- (1) At 600°C, CO cannot reduce FeO (2) At 600°C, CO can reduce ZnO (3) At 600°C, C can reduce ZnO (4) At 600°C, C can reduce FeO

Q35.When the hydrogen ion concentration [H+]changes by a factor of 1000 , the value of pH of the solution (1) increases by 1000 units (2) decreases by 3 units (3) decreases by 2 units (4) increases by 2 units

Q36.Choose the correct set of reagents for the following conversion transPh - CH = CH - CH3 → cis Ph - CH = CH - CH3 (1) Br2, alc KOH, NaNH2, NaLiqNH3 (2) Br2, alc KOH, NaNH2, H2 Lindlar Catalyst (3) Br2, aqKOH, NaNH2, H2 Lindlar Catalyst (4) Br2, aq KOH, NaNH2, NaLiqNH3

Q36.For complete combustion of ethene, C2H4( g) + 3O2( g) →2 CO2( g) + 2H2O(l) the amount of heat produced as measured in bomb calorimeter is 1406 kJ mol−1 at 300 K. The minimum value of TΔS needed to reach equilibrium is (−) kJ. (Nearest integer) Given: R = 8. 3 J K−1 mol−1

Q36.If the pKa of lactic acid is 5 , then the pH of 0. 005 M calcium lactate solution at 25° C is __________ × 10–1 (Nearest integer)

Q37.One mole of an ideal gas at 350 K is in a 2. 0 L vessel of thermally conducting walls, which are in contact with the surroundings. It undergoes isothermal reversible expansion from 2. 0 L to 3. 0 L against a constant pressure of 4 atm. The change in entropy of the surroundings (ΔS) is _____ J K–1 (Nearest integer) Given: R = 8. 314 J K−1 mol−1 . JEE Main 2023 (12 Apr Shift 1) JEE Main Previous Year Paper

Q39.The product formed in the following multistep reaction is: (1) (2) (3) (4)

Q39.The correct order for acidity of the following hydroxyl compound is (A) CH3OH (B) CH33COH (C) (D) (E) Choose the correct answer from the options given below: (1) C > E > D > B > A (2) E > D > C > B > A (3) D > E > C > A > B (4) E > C > D > A > B

Q40. KMnO4 is titrated with ferrous ammonium sulphate hexahydrate in presence of dilute H2 SO4. Number of water molecules produced for 2 molecules of KMnO4 is _______ Q41. 20 mL of calcium hydroxide was consumed when it was reacted with 10 mL of unknown solution of H2 SO4. Also 20 mL standard solution of 0. 5 M HCl containing 2 drops of phenolphthalein was titrated with calcium hydroxide, the mixture showed pink colour when burette displayed the value of 35. 5 mL whereas the burette showed 25. 5 mL initially. The concentration of H2 SO4 is _______M. (Nearest integer)

Q43.Following chromatogram was developed by adsorption of compound ' A ' on a 6 cm TLC glass plate. Retardation factor of the compound ' A' is _____ ×10−1 . Q44. 17 mg of a hydrocarbon (M.F. C10H16 ) takes up 8. 40 mL of the H2 gas measured at 0°C and 760 mm of Hg. Ozonolysis of the same hydrocarbon yields CH3 −C −CH3, H −C −H, H −C −CH2 −CH2 −C −C −H || || || || || O O O O O The number of double bond/s present in the hydrocarbon is

Q44.A hydrocarbon 'X' with formula C6H8 uses two moles of H2 on catalystic hydrogenation of its one mole. On ozonolysis, 'X' yields two moles of methane dicarbaldehyde. The hydrocarbon 'X' is : (1) hexa- 1, 3, 5 -triene (2) 1-methylcyclopenta- 1, 4−diene (3) cyclohexa −1, 3−diene (4) cyclohexa −1, 4−diene

Q45.The correct order of the number of unpaired electrons in the given complexes is (A) [Fe ( CN ) 3 - 6] (B) FeF6 3 - (C) CoF6 3 - (D) Cr ( oxalate 3 - ) 3 (E) Ni ( CO ) 4 Choose the correct answer from the options given below: (1) E < A < D < C < B (2) E < A < B < D < C (3) A < E, C < B < D (4) A < E < D < C < B

Q46.Solid Lead nitrate is dissolved in 1 litre of water. The solution was found to boil at 100. 15°C. When 0. 2 mol of NaCl is added to the resulting solution, it was observed that the solution froze at −0. 8°C. The solutbility product of PbCl2 formed is _____ ×10−6 at 298 K. (Nearest integer) Given : Kb = 0. 5K kg mol−1 and Kf = 1. 8 kg mol−1 . Assume molality to be equal to molarity in all cases. JEE Main 2023 (29 Jan Shift 1) JEE Main Previous Year Paper

Q46.The total number of stereoisomers for the complex [Cr ( ox ) 2ClBr] 3 – (where ox = oxalate) is (1) 3 (2) 2 (3) 4 (4) 1

Q47.If the boiling points of two solvents X and Y (having same molecular weights) are in the ratio 2: 1 and their enthalpy of vaporizations are in the ratio 1 : 2, then the boiling point elevation constant of X is m times the boiling point elevation constant of Y . The value of m is (nearest integer).

Q47.L-isomer of tetrose X ( C4H8O4 ) gives positive Schiff’s test and has two chiral carbons. On acetylation ‘X’ yields triacetate. ‘X’ also undergoes following reactions. (1) (2) (3) (4) JEE Main 2023 (11 Apr Shift 1) JEE Main Previous Year Paper Q48. ‘A’ and ‘B’ in the above reactions are: (1) (2) (3) (4) Q49. 'X' (1) (2) (3) (4)

Q47.Evaluate the following statements for their correctness. A. The elevation in boiling point temperature of water will be same for 0. 1 M NaCl and 0. 1 M urea. B. Azeotropic mixture boil without change in their composition. C. Osmosis always takes place from hypertonic to hypotonic solution. D. The density of 32% H2 SO4 solution having molarity 4. 09 M is approximately 1. 26 g mL–1 . E. A negatively charged sol is obtained when KI solution is added to silver nitrate solution. Choose the correct answer from the options given below: (1) B and D only (2) B, D and E only (3) A and C only (4) A, B and C only

Q47.Consider the following reaction ( i ) dil . NaOH Propanal + Methanal = → Product B (ii) Δ(iii) NaCN(iv) H3O+ ( C5H8O3 ) The correct statement for product 𝐵 is. It is JEE Main 2023 (31 Jan Shift 1) JEE Main Previous Year Paper (1) optically active and adds one mole of bromine (2) racemic mixture and is neutral (3) racemic mixture and gives a gas with saturated (4) optically active alcohol and is neutrall NaHCO3 solution

Q49.Match List I with List II: List I (Monomer) List II (Polymer) (A) Tetrafluoroethene (I) Orlon (B) Acrylonitrile (II) Natural rubber (C) Caprolactam (III) Teflon (D) Isoprene (IV) Nylon- 6 Choose the correct answer from the options given below: (1) (A) −(III), (B) −(I), (C) −(IV), (D) −(II) (2) (A) −(IV), (B) −(I), (C) −(II), (D) −(III) (3) (A) −(III), (B) −(IV), (C) −(II), (D) −(I) (4) (A) −(II), (B) −(III), (C) −(IV), (D) −(I)

Q49.Consider the following reaction that goes from A to B in three steps as shown below: Choose the correct option Number of Rate Number of Activated determining Intermediates Complexes step (1) 2 3 I (2) 2 3 III (3) 2 3 II (4) 3 2 II (1) (1) (2) (2) (3) (3) (4) (4)

Q50.Given below are two statements : Statement I : Noradrenaline is a neurotransmitter. Statement II : Low level of noradrenaline is not the cause of depression in human. In the light of the above statements, choose the correct answer from the options given below (1) Both statement 1 and 2 are correct.. (2) Statement 1 is correct but statement 2 is incorrect (3) Statement 1 is incorrect but statement 2 is correct (4) Both statement 1 and 2 are correct

Q51.Given below are two statements, one is labelled as Assertion A and the other is labelled as Reasom R. Assertion A: A solution of the product obtained by heating a mole of glycine with a mole of chlorine in presence of red phosphorous generates chiral carbon atom. Reason R: A molecule with 2 chiral carbons is always optically active. In the light of above statements, chose the correct answer from the options given below: (1) A is true but R is false (2) Both A and R are true but R is the correct explaination of A (3) A is false but R is true (4) Both A and R are true but R is NOT the correct explaination of A

Q52.Match List I with List II JEE Main 2023 (25 Jan Shift 2) JEE Main Previous Year Paper List I List II Coordination entity Wavelength of light absorbed in nm A [CoCl (NH3)5]2+ I. 310 B [Co (NH3)6]3+ II. 475 C [Co(CN)6]3− III. 535 D [Cu (H2O)4]2+ IV. 600 Choose the correct answer from the options given below :- (1) A −IV, B −I, C −III, D −II (2) A −III, B −II, C −I, D −IV (3) A −III, B −I, C −II, D −IV (4) A − II, B −III, C −IV, D −I

Q53.Which of the following complex is octahedral, diamagnetic and the most stable? (1) Na3[CoCl6] (2) [Ni (NH3)6] Cl2 (3) K3[Co(CN)6] (4) [Co (H2O)6] Cl2