Practice Questions

Q51.If the work function of a metal is 6. 63 × 10−19 J, the maximum wavelength of the photon required to remove a photoelectron from the metal is____ nm. Nearest integer) [Given : h = 6. 63 × 10−34 J s, and c = 3 × 108 m s−1 ]

Q51.Amongst the following the number of oxide(s) which are paramagnetic in nature is Na2 O, KO2, NO2, N2O, ClO2, NO, SO2, Cl2 O

Q51.A protein 'A' contains 0 . 30% of glycine (molecular weight 75). The minimum molar mass of the protein 'A' is____ × 103 g mol-1 [nearest integer] JEE Main 2022 (25 Jun Shift 2) JEE Main Previous Year Paper

Q51.A box contains 0. 90 g of liquid water in equilibrium with water vapour at 27°C. The equilibrium vapour pressure of water at 27°C 32. 0 Torr. When the volume of the box is increased, some of the liquid water evaporates to maintain the equilibrium pressure. If all the liquid water evaporates, then the volume of the box must be ______ litre. [nearest integer] (Given: R = 0. 082 L atm K−1 mol−1 _ (Ignore the volume of the liquid water and assume water vapours behave as an ideal gas.) Q52. 2. 2 g of nitrous oxide (N2O) gas is cooled at a constant pressure of 1 atm from 310 K to 270 K causing the compression of the gas from 217. 1 mL to 167. 75 mL. The change in internal energy of the process, △U is ′−x′J. The value of ′x′ is _____. [nearest integer] (Given: atomic mass of N = 14 g mol−1 and of O = 16 g mol−1 . Molar heat capacity of N2O is 100 JK−1 mol−1 )

Q51.The number of N atoms in 681 g of C7H5N3O6 is 𝑥× 1021. The value of x is NA = 6 . 02 × 1023 mol-1 (Nearest Integer) JEE Main 2022 (25 Jun Shift 1) JEE Main Previous Year Paper Q52.1 L aqueous solution of H2SO4 contains 0 . 02 m mol H2SO4 . 50% of this solution is diluted with deionized water to give 1 L solution A. In solution A, 0 . 01 m mol of H2SO4 are added. Total m mols of H2SO4 in the final solution is____ × 10-3 m moles.

Q51.Consider an imaginary ion 48X322 - . The nucleus contains 'a' % more neutrons than the number of electrons in the ion. The value of 'a' is

Q51.If the uncertainty in velocity and position of a minute particle in space are, 2. 4 × 10−26(ms−1) and 10−7(m) respectively. The mass of the particle in g is___(Nearest integer) (Given : h = 6. 626 × 10−34 Js) Q52. 2 NOCl(g) ⇌2 NO(g) + Cl2(g) In an experiment, 2. 0 moles of NOCl was placed in a one-litre flask and the concentration of NO after equilibrium established, was found to be 0. 4 mol /L. The equilibrium constant at 30 °C is_____ ×10−4 .

Q51.Geraniol, a volatile organic compound, is a component of rose oil. The density of the vapour is 0. 46 gL−1 at 257 °C and 100 mmHg . The molar mass of geraniol is (Nearest Integer) [Given R = 0. 082 L atm K−1 mol−1 ] Q52. 17. 0 g of NH3 completely vapourises at −33. 42 °C and 1 bar pressure and the enthalpy change in the process is 23. 4 kJ mol−1 . The enthalpy change for the vapourisation of 85 g of NH3 under the same conditions is kJ.

Q51.The complete combustion of 0. 492 g of an organic compound containing ' C', ' H' and ' O' gives 0. 793 g of CO2 and 0. 442 g of H2O. The percentage of oxygen composition in the organic compound is____.(nearest integer) Q52. 100 g of an ideal gas is kept in a cylinder of 416 L volume at 27 °C under 1. 5 bar pressure. The molar mass of the gas is g mol−1 . (Nearest integer) (Given : R = 0. 083 L bar K−1 mol−1 )

Q51.In the given reaction, X + Y + 3Z ⇄XYZ3 if one mole of each of X and Y with 0 . 05 mol of Z gives compound XYZ3. (Given : Atomic masses of X, Y and Z are 10,20 and 30amu, respectively). The yield of XYZ3 is____g.

Q52.When the excited electron of a H atom from n = 5 drops to the ground state, the maximum number of emission lines observed are

Q52.If the wavelength for an electron emitted from H− atom is 3. 3 × 10−10 m, then energy absorbed by the electron in its ground state compared to minimum energy required for its escape from the atom, is____times. [Given : h = 6. 626 × 10−34 Js, Mass of electron = 9. 1 × 10−31 ]

Q52.Consider the following set of quantum numbers. n l m1 A 3 3 −3 B 3 2 −2 C 2 1 +1 D 2 2 +2 JEE Main 2022 (27 Jun Shift 2) JEE Main Previous Year Paper The number of correct sets of quantum numbers is

Q52.When 600 mL of 0. 2M HNO3 is mixed with 400 mL of 0. 1M NaOH solution in a flask, the rise in temperature of the flask is_____ ×10−2 °C (Enthalpy of neutralisation = 57 kJ mol−1 and Specific heat of water = 4. 2 JK−1 g−1 ) (Neglect heat capacity of flask)

Q52.The pressure of a moist gas at 27°C is 4 atm. The volume of the container is doubled at the same temperature. The new pressure of the moist gas is … × 10-1 atm. (Nearest integer) (Given: The vapour pressure of water at 27°C is 0 . 4 atm)

Q52.According to MO theory, number of species/ions from the following having identical bond order is____ CN−, NO+, O2, O+2 , O2+2

Q52.A 10 g mixture of hydrogen and helium is contained in a vessel of capacity 0 . 0125 m3 at 6 bar and 27 °C. The mass of helium in the mixture is ..... g. (Given : R = 8 . 3JK-1 mol-1 (Atomic masses of H and He are 1u and 4u, respectively)

Q52.A 0. 166 g sample of an organic compound was digested with conc. H2 SO4 and then distilled with NaOH. The ammonia gas evolved was passed through 50. 0 mL of 0. 5 N H2 SO4 . The used acid required 30. 0 mL of 0. 25 N NaOH for complete neutralization. The mass percentage of nitrogen in the organic compound is

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)

Q52.The number of molecule(s) or ion(s) from the following having non-planar structure is______. NO−3 , H2O2, BF3, PCl3, XeF4 , SF4, XeO3, PH+4 , SO3, [Al (OH)4]−

Q52.The hybridization of P exhibited in PF5 is spx dy . The value of y is Q53. 4. 0 L of an ideal gas is allowed to expand isothermally into vacuum until the total volume is 20 L. The amount of heat absorbed in this expansion is L atm.

Q52.The moles of methane required to produce 81 g of water after complete combustion is____ ×10−2 mol. [nearest integer]

Q52.Consider, PF5, BrF5, PCl3, SF6, ICl4 -, ClF3 and IF5 Amongst the above molecule(s) ion(s), the number of molecule(s)/ion(s) having sp3d2 hybridisation is Q53.'x' g of molecular oxygen O2 is mixed with 200 g of neon Ne. The total pressure of the nonreactive mixture of O2 and Ne in the cylinder is 25 bar. The partial pressure of Ne is 20 bar at the same temperature and volume. The value of 'x' is [Given: Molar mass of O2 = 32 g mol-1. Molar mass of Ne = 20 g mol-1] JEE Main 2022 (29 Jul Shift 2) JEE Main Previous Year Paper Q54.1 . 80 g of solute A was dissolved in 62 . 5 cm3 of ethanol and freezing point of the solution was found to be 155 . 1 K. The molar mass of solute A is gmol-1. [Given: Freezing point of ethanol is 156 . 0 K. Density of ethanol is 0 . 80 g cm-3. Freezing point depression constant of ethanol is 2 . 00 K kg mol-1]

Q52.For complete combustion of methanol CH3 OH(l) + 32 O2(g) →CO2(g) + 2H2O(l) the amount of heat produced as measured by bomb calorimeter is 726 kJ mol−1 at 27 °C . The enthalpy of combustion for the reaction is −x kJ mol−1 , where x is JEE Main 2022 (26 Jun Shift 1) JEE Main Previous Year Paper integer) (Given : R = 8. 3 JK−1 mol−1 ) Q53. 50 mL of 0. 1 M CH3 COOH is being titrated against 0. 1 M NaOH . When 25 mL of NaOH has been added, the pH of the solution will be____ ×10−2 . (Nearest integer) (Given : pKa(CH3 COOH) = 4. 76) log 2 = 0. 30 log 3 = 0. 48 log 5 = 0. 69 log 7 = 0. 84 log 11 = 1. 04

Q52.On complete combustion of 0 . 492 g of an organic compound containing C, H and O, 0 . 7938 g of CO2 and 0 . 4428 g of H2O was produced. The % composition of oxygen in the compound is____. (Nearest Integer)