Practice Questions

Q36.Water decomposes at 2300 K H2O(g) →H2(g) + 12 O2(g) The percent of water decomposing at 2300 K and 1 bar is _____ (Nearest integer). Equilibrium constant for the reaction is 2 × 10−3 at 2300 K

Q36.At 600 K, the root mean square (rms) speed of gas X (molar mass = 40) is equal to the most probable speed of gas Y at 90 K. The molar mass of the gas Y is _____ g mol–1 . (Nearest integer)

Q36.The total number of intensive properties from the following is........... Volume, Molar heat capacity, molarity, Eocell ,Gibbs free energy change, Molar mass, Mole Q37. 4. 5 moles each of hydrogen and iodine is heated in a sealed ten litre vessel.At equilibrium, 3 moles of HI were found. The equilibrium constant for H2(g) + I2(g) ⇌2 HI(g) is ........

Q36.Consider the following data Heat of combustion of H2(g) = –241. 8 kJ mol–1 Heat of combustion of C(s) = –393. 5 kJ mol–1 Heat of combustion of C2H5 OH(l)= –1234. 7 kJ mol–1 The heat of formation of C2H5 OH(l) is (–) _____ kJ mol–1 (Nearest integer).

Q36.Given below are two reactions, involved in the commercial production of dihydrogen H2. The two reactions are carried out at temperature “T1” and “T2”, respectively T1 Cs + H2Og ⟶COg + H2g T2 COg + H2Og CatalystCO2g + H2g The temperatures T1 and T2 are correctly related as (1) T1 = T2 (2) T1 < T2 (3) T1 = 100 K, T2 = 1270 K (4) T1 > T2

Q36.Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : An aqueous solution of KOH when for volumetric analysis, its concentration should be checked before the use. Reason (R) : On aging, KOH solution absorbs atmospheric CO2 . In the light of the above statements, choose the correct answer from the options given below. (1) (A) is not correct but (R) is correct (2) Both (A) and (R) are correct but (R) is not the correct explanation of (A) (3) Both (A) and (R) are correct and (R) is the (4) (A) is correct but (R) is not correct correct explanation of (A)

Q36.The strength of 50 volume solution of hydrogen peroxide is _____ g/L (Nearest integer). Given: Molar mass of H2O2 is 34 g mol−1 Molar volume of gas at STP = 22. 7 L.

Q36.Match List I with List II List I List II Elements Colour imparted to the flame A K I Brick Red B Ca II Violet C Sr III Apple Green D Ba IV Crimson Red Choose the correct answer from the options given below: (1) A-II, B-I, C-III, D-IV (2) A-II, B-IV, C-I, D-III (3) A-II, B-I, C-IV, D-III (4) A-IV, B-III, C-II, D-I

Q36.For a good quality cement, the ratio of silica to alumina is found to be (1) 1. 5 (2) 4. 5 (3) 2 (4) 3

Q36.Among the following compounds, the one which shows highest dipole moment is (1) (2) (3) (4)

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)

Q36.Match List I with List II List I List II A. Cobalt catalyst I. (H2 + Cl2) production B. Syngas II. Water gas production C. Nickel catalyst III. Coal gasification D. Brine solution IV. Methanol production Choose the correct answer from the options given below:- JEE Main 2023 (25 Jan Shift 2) JEE Main Previous Year Paper (1) A-IV, B-I, C-II, D-III (2) A-IV, B-III, C-I, D-II (3) A-II, B-III, C-IV, D-I (4) A-IV, B-III, C-II, D-I

Q36.Match List-I with List-II: List-I List-II A. K I. Thermonuclear reactions B. KCI II. Fertilizer C. KOH III. Sodium potassium pump D. Li IV. Absorbent of CO2 (1) A(III), B(II), C(IV), D(I) (2) A(III), B(IV), C(II), D(I) (3) A(IV), B(I), C(III), D(II) (4) A(IV), B(III), C(I), D(II)

Q36.How can photochemical smog be controlled? (1) By using tall chimneys (2) By complete combustion of fuel (3) By using catalytic converters in (4) By using catalyst the automobiles/industry

Q36.Match List-I with List-II. List-I List-II Element detected Reagent used/Product formed A Nitrogen I Na2FeCN5NO B Sulphur II AgNO3 C Phosphorus III Fe4FeCN63 D Halogen IV NH42MoO4 Choose the correct answer from the options given below: (1) A →III; B →I; C →IV; D →II (2) A →II; B →IV; C →I; D → III (3) A →IV; B →II; C →I; D →III (4) A →II; B →I; C →IV; D →III

Q36.Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). JEE Main 2023 (30 Jan Shift 1) JEE Main Previous Year Paper Assertion (A): In expensive scientific instruments, silica gel is kept in watch-glasses or in semipermeable membrane bags. Reason (R): Silica gel adsorbs moisture from air via adsorption, thus protects the instrument from water corrosion (rusting) and / or prevents malfunctioning. In the light of the above statements, choose the correct answer from the options given below: (1) (A) is false but (R) is true (2) (A) is true but (R) is false (3) Both (A) and (R) are true and (R) is the correct (4) Both (A) and (R) are true but (R) is not the explanation of (A) correct explanation of (A)

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.The volume of HCl, containing 73g L−1 , required to completely neutralise NaOH obtained by reacting 0. 69 g of metallic sodium with water, is _____ mL. (Nearest Integer) (Given : molar Masses of Na, Cl, O, H are 23, 35. 5, 16 and 1g mol−1 respectively)

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.Enthalpies of formation of CCl4( g), H2O(g), CO2( g) and HCl are −105, −242, −394 and −92 kJ mol−1 respectively. The magnitude of enthalpy of the reaction given below is kJmol−1 . (nearest integer) CCl4( g) + 2H2O(g) →CO2( g) + 4 HCl(g)

Q36.Better method for preparation of BeF2, among the following is (1) ∆ (2) 𝛥 BeO + C + F2 ⟶BeF2 NH42BeF4 ⟶BeF2 (3) ∆ (4) Δ Be + F2 ⟶BeF2 BeH2 + F2 ⟶BeF2

Q37.Chlorides of which metal are soluble in organic solvents: (1) Ca (2) Mg (3) K (4) Be JEE Main 2023 (30 Jan Shift 2) JEE Main Previous Year Paper

Q37.Which of the following conformations will be the most stable? JEE Main 2023 (25 Jan Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)

Q37.Which of the following is true about freons? (1) These are chlorofluorocarbon compounds (2) These are chemicals causing skin cancer (3) These are radicals of chlorine and chlorine (4) All radicals are called freons monoxide

Q37.Incorrect statement for the use of indicator in acid-base titration is: JEE Main 2023 (31 Jan Shift 2) JEE Main Previous Year Paper (1) Methyl orange may be used for a weak acid vs (2) Phenolphthalein may be used for a strong acid vs weak bas titration. strong base titration. (3) Methyl orange is a suitable indicator for a strong (4) Phenolphthalein is a suitable indicator for a weak acid vs weak base titration. acid vs strong base titration.