Practice Questions

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.When 800 mL of 0. 5M nitric acid is heated in a beaker, its volume is reduced to half and 11. 5 g of nitric acid is evaporated. The molarity of the remaining nitric acid solution is x × 10−2M. (Molar mass of nitric acid is 63 g mol−1 )

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.How many of the following molecules are with non-zero net dipole moment, NH3 , HCl, H2O , BeF2, BH3, CCl4

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

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, 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]

Q53.Among the following the number of state variable is Internal energy (U) Volume (V) Heat (q) Enthalpy (H)

Q53.Number of grams of bromine that will completely react with 5 . 0 g of pent-1-ene is____ × 10-2 g. (Atomic mass of Br = 80 g / mol) [Nearest integer]

Q53.When 5 moles of He gas expand isothermally and reversibly at 300 K from 10 litre to 20 litre, the magnitude of the maximum work obtained is J. [nearest integer ] (Given : R = 8. 3 J K−1 mol−1 and log 2 = 0. 3010)

Q53.The molar heat capacity for an ideal gas at constant pressure is 20. 785 J K−1 mol−1 . The change in internal energy is 5000 J upon heating it from 300 K to 500 K. The number of moles of the gas at constant volume JEE Main 2022 (27 Jul Shift 1) JEE Main Previous Year Paper is____ (Given: R = 8. 314 J K−1 mol−1 )

Q53.Total number of possible stereoisomers of dimethyl cyclopentane is

Q53.A rigid nitrogen tank stored inside a laboratory has a pressure of 30 atm at 06: 00 am when the temperature is 27 °C. At 03: 00pm, when the temperature is 45 °C, the pressure in the tank will be _____ atm. [nearest integer]

Q53.Number of electrophillic centres in the given compound is___

Q53.For combustion of one mole of magnesium in an open container at 300 K and 1 bar pressure, ΔCH⊖= −601. 70 kJ mol−1 , the magnitude of change in internal energy for the reaction is kJ. (Nearest integer) (Given : R = 8. 3 J K−1 mol−1 ) Q54. 0. 01 MKMnO4 solution was added to 20. 0 mL of 0. 05M Mohr 's salt solution through a burette. The initial reading of 50 mL burette is zero. The volume of KMnO4 solution left in the burette after the end point is....... mL. (nearest integer) JEE Main 2022 (28 Jun Shift 2) JEE Main Previous Year Paper

Q53.For the reaction given below: CoCl3. xNH3 + AgNO3(aq) → If two equivalents of AgCl precipitate out, then the value of x will be _______

Q53.If the solubility product of PbS is 8 × 10−28 , then the solubility of PbS in pure water at 298 K is x × 10−16 mol L−1 . The value of x is____ (Nearest integer) [Given √2 = 1. 41]

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 )

Q53.The wavelength of an electron and a neutron will become equal when the velocity of the electron is x times the velocity of neutron. The value of x is____(the nearest integer)(Mass of electron is 9. 1 × 10−31 kg and mass of neutron is 1. 6 × 10−27 kg)

Q53.For the reaction H2F2g →H2g + F2g JEE Main 2022 (26 Jul Shift 2) JEE Main Previous Year Paper ΔU = - 59 . 6 kJ mol-1 at 27 °C The enthalpy change for the above reaction is - ____ kJmol-1 (nearest integer) (Given : R = 8 . 314JK-1 mol-1) . Q54.20 mL of 0 . 02 M hypo solution is used for the titration of 10 mL of copper sulphate solution, in the presence of excess of KI using starch as an indicator. The molarity of Cu2 + is found to be _____ × 10-2M (nearest integer) Given : 2Cu2 + + 4I- →Cu2I2 + I2I2 + 2S2O3-2 → 2I— + S4O6-2