Practice Questions

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]

Q54.The neutralization occurs when 10 mL of 0 . 1 M acid 'A' is allowed to react with 30 mL of 0 . 05 M base MOH2. The basicity of the acid 'A' is [M is a metal]

Q54.Observe structures of the following compounds The total number of structures/compounds which possess asymmetric carbon atoms is Q55. 1. 2 mL of acetic acid is dissolved in water to make 2. 0 L of solution. The depression in freezing point observed for this strength of acid is 0. 0198 °C . The percentage of dissociation of the acid is (Nearest integer) [Given : Density of acetic acid is 1. 02 g mL−1 Molar mass of acetic acid is 60 g mol−1 Kf(H2O) = 1. 85 K kg mol−1 ]

Q54.At 310 K, the solubility of CaF2 in water is 2. 34 × 10−3 g/100 mL . The solubility product of CaF2 is ---- ×10−8(mol /L)3 (nearest integer). (Given molar mass : CaF2 = 78 g mol−1 ) Q55. 20 mL of 0. 02 MK2 Cr2 O7 solution is used for the titration of 10 mL of Fe2+ solution in the acidic medium. The molarity of Fe2+ solution is____ ×10−2M

Q54.In bromination of Propyne, with Bromine 1, 1, 2, 2-tetrabromopropane is obtained in 27% yield. The amount of 1, 1, 2, 2 tetrabromopropane obtained from 1 g of Bromine in this reaction is_____ ×10−1 g . (Molar Mass : Bromine = 80 g/ mol)

Q54.Metal deficiency defect is shown by Fe0.93 O. In the crystal, some Fe2+ cations are missing and loss of positive charge is compensated by the presence of Fe3+ ions. The percentage of Fe2+ ions in the Fe0.93 O crystals is____(Nearest integer)

Q54.A mixture of hydrogen and oxygen contains 40% hydrogen by mass when the pressure is 2. 2 bar. The partial pressure of hydrogen is bar. Q55. 2. 4 g coal is burnt in a bomb calorimeter in excess of oxygen at 298 K and 1 atm pressure. The temperature of the calorimeter rises from 298 K to 300 K. The enthalpy change during the combustion of coal is −x kJ mol−1 . The value of x is_____(Given : Heat capacity of bomb calorimeter 20. 0 kJK−1 . Assume coal to be pure carbon)

Q54.While estimating the nitrogen present in an organic compound by Kjeldahl's method, the ammonia evolved from 0 . 25 g of the compound neutralized 2 . 5 mL of 2MH2SO4. The percentage of nitrogen present in organic compound is _____ .

Q54. A fish swimming in water body when taken out from the water body is covered with a film of water of weight 36 g . When it is subjected to cooking at 100 °C, then the internal energy for vaporization in kJmol−1 is integer] [Assume steam to be an ideal gas. Given ΔvapH⊖ for water at 373 K and 1 bar is 41. 1 kJ mol−1 : R = 8. 31 J K−1 mol−1 ] Q55. 40% of HI undergoes decomposition to H2 and I2 at 300 K. ΔGΘ for this decompostion reaction at one atmopsphere pressure is____ Jmol−1 -[nearest integer] (Use R = 8. 31 JK−1 mol−1; log 2 = 0. 3010, ln 10 = 2. 3, log 3 = 0. 477)

Q54.The longest wavelength of light that can be used for the ionisation of lithium ion $\mathrm{(Li^{2+})}$ is x × 10-8 m. The value of x is (Nearest Integer) (Given : Energy of the electron in the first shell of the hydrogen atom is -2 . 2 × 10-18 J; h = 6 . 63 × 10-34Js and c = 3 × 108 ms-1)

Q54.A gas ( Molar mass = 280 g mol−1 ) was burnt in excess O2 in a constant volume calorimeter and during combustion the temperature of calorimeter increased from 298. 0 K to 298. 45 K . If the heat capacity of calorimeter is 2. 5 kJ K−1 and enthalpy of combustion of gas is 9 kJ mol−1 then amount of gas burnt is____ g .

Q54.Ka for butyric acid C3H7COOH is 2 × 10-5. ThepH of 0 . 2M solution of butyric acid is____ × 10-1. (Nearest integer) [Given log2 = 0 . 30]

Q54.The number of chiral alcohol(s) with molecular formula C4H10O is ________ (Assume stereoisomers as different chiral alcohols)

Q54.A sealed flask with a capacity of 2 dm3 contains 11 g of propane gas. The flask is so weak that it will burst if the pressure becomes 2 MPa. The minimum temperature at which the flask will burst is ∘C. [Nearest integer] (Given: R = 8. 3 J K−1 mol−1 . Atomic masses of C and H are 12u and 1u respectively.) (Assume that propane behaves as an ideal gas.)

Q55. BeO reacts with HF in presence of ammonia to give [A] which on thermal decomposition produces [B] and ammonium fluoride. Oxidation state of Be in [A] is Q56. 0. 25 g of an organic compound containing chlorine gave 0. 40 g of silver chloride in Carius estimation. The percentage of chlorine present in the compound is [in nearest integer] (Given: Molar mass of Ag is 108 g mol−1 and that of Cl is 35. 5 g mol−1 )

Q55.The standard entropy change for the reaction 4Fes + 3O2g →2Fe2O3s is -550 J K-1 at 298 K [Given : The standard enthalpy change for the reaction is -165 kJ mol-1]. The temperature in K at which the reaction attains equilibrium is (Nearest Integer)

Q55.Atoms of element X form hcp lattice and those of element Y occupy 32 of its tetrahedral voids. The percentage of element X in the lattice is (Nearest integer)

Q55.On reaction with stronger oxidizing agent like KIO4 , hydrogen peroxide oxidizes with the evolution of O2 . The oxidation number of I in KIO4 changes to

Q55.The normality of H2 SO4 in the solution obtained on mixing 100 mL of 0. 1M H2 SO4 with 50 mL of 0. 1M NaOH is____ ×10−1 N .

Q55.The elevation in boiling point for 1 molal solution of non-volatile solute A is 3 K. The depression in freezing point for 2 molal solution of A in the same solvent is 6 K. The ratio of Kb and Kf i.e., Kb / Kf is 1: X. The value of X is

Q55.A 0. 5 percent solution of potassium chloride was found to freeze at −0. 24 °C. The percentage dissociation of potassium chloride is (Nearest integer) (Molal depression constant for water is 1. 80 K kg mol−1 and molar mass of KCl is 74. 6 g mol−1 )

Q55.While performing a thermodynamics experiment, a student made the following observations, HCl + NaOH →NaCl + H2OΔH = −57. 3 kJ mol−1 CH3 COOH + NaOH →CH3 COONa + H2O ΔH = −55. 3 kJ mol−1 . JEE Main 2022 (25 Jul Shift 2) JEE Main Previous Year Paper The enthalpy of ionization of CH3 COOH as calculated by the student is kJ mol−1 .

Q55.Ionic radii of cation A+ and anion B− are 102 and 181 pm respectively. These ions are allowed to crystallize into an ionic solid. This crystal has cubic close packing for B−. A+ is present in all octahedral voids. The edge length of the unit cell of the crystal AB is___ pm .

Q55.A solution of Fe2SO43 is electrolyzed for 'x' min with a current of 1 . 5 A to deposit 0 . 3482 g of Fe. The value of x is - [nearest integer] Given : 1 F = 96500 Cmol-1. Atomic mass of Fe = 56 gmol-1

Q55.Two elements A and B which form 0. 15 moles of A2B and AB3 type compounds. If both A2B and AB3 weigh equally, then the atomic weight of A is____times of atomic weight of B. Q56. 2 g of a non-volatile non-electrolyte solute is disolved in 200 g of two different solvents A and B whose ebullioscopic constants are in the ratio of 1 : 8. The elevation in boiling points of A and B are in the ratio x (x : y). The value of y is____(Nearest Integer) y