Practice Questions

Q56.The number of non-ionisable protons present in the product B obtained from the following reaction is___ C2H5OH + PCl3 →C2H5Cl + A A + PCl3 →B

Q56.A radioactive element has a half life of 200 days. The percentage of original activity remaining after 83 days is____(Nearest integer) (Given : antilog 0. 125 = 1. 333, antilog 0. 693 = 4. 93) Q57. [Fe (CN)6]4− [Fe (CN)6]3− [Ti (CN)6]3− [Ni (CN)4]2− [Co (CN)6]3− Among the given complexes, number of paramagnetic complexes is

Q56.If O2 gas is bubbled through water at 303 K, the number of millimoles of O2 gas that dissolve in 1 litre of water is____(Nearest integer) (Given : Henry's Law constant for O2 at 303 K is 46. 82k bar and partial pressure of O2 = 0. 920 bar) (Assume solubility of O2 in water is too small, nearly negligible)

Q56.The vapour pressures of two volatile liquids A and B at 25 °C are 50 Torr and 100 Torr, respectively. If the liquid mixture contains 0. 3 mole fraction of A, then the mole fraction of liquid B in the vapour phase is 17x . The value of x is

Q56.At 298 K, the equilibrium constant is 2 × 1015 for the reaction: Cu(s) + 2 Ag+(aq) ⇌Cu2+(aq) + 2 Ag(s) The equilibrium constant for the reaction 2 1 Cu2+(aq) + Ag(s) ⇌12 Cu(s) + Ag+(aq) is x × 10−8 . The value of x is ______. (Round off the answer to the nearest integer) JEE Main 2022 (26 Jul Shift 1) JEE Main Previous Year Paper

Q56.Assuming 1μg of trace radioactive element X with a half life of 30 years is absorbed by a growing tree. The amount of X remaining in the tree after 100 years is_____ × 10-1μg. [Given : ln10 = 2 . 303; log2 = 0 . 30]

Q56.In a solid AB, A atoms are in ccp arrangement and B atoms occupy all the octahedral sites. If two atoms from the opposite faces are removed, then the resultant stoichiometry of the compound is AxBy . The value of x is [nearest integer]

Q56.At 345 K, the half life for the decomposition of a sample of a gaseous compound initially at 55 . 5 kPa was 340 s. When the pressure was 27 . 8 kPa, the half life was found to be 170 s. The order of the reaction is - [integer answer]

Q57.The half life for the decomposition of gaseous compound A is 240 s when the gaseous pressure was 500 Torr initially. When the pressure was 250 Torr, the half life was found to be 4 . 0 min. The order of the reaction is _____ (Nearest integer)

Q57.The equation k = (6. 5 × 1012 s−1)e−26000 K/T is followed for the decomposition of compound A. The activation energy for the reaction is ____ KJ mol−1 . [nearest integer] (Given: R = 8. 314 J K−1 mol−1 )

Q57.The spin-only magnetic moment value of the compound with strongest oxidizing ability among MnF4, MnF3 and MnF2 is_____ B . M (nearest integer)

Q57.Consider the following sulphure based oxoacids. H2SO3, H2SO4, H2S2O8 and H2S2O7. Amongst these oxoacids, the number of those with peroxo O - Obond is

Q57.When 200 mL of 0. 2 M acetic acid is shaken with 0. 6 g of wood charcoal, the final concentration of acetic acid after adsorption is 0. 1 M. The mass of acetic acid adsorbed per gram of carbon is g .

Q57.The osmotic pressure exerted by a solution prepared by dissolving 2. 0 g of protein of molar mass 60 kg mol−1 in 200 mL of water at 27 °C is____ Pa . [integer value] (use R = 0. 083 L bar mol−1 K−1 )

Q57.The solubility product of a sparingly soluble salt A2X3 is 1. 1 × 10−23 . If specific conductance of the solution is 3 × 10−5 Sm−1 , the limiting molar conductivity of the solution is x × 10−3 S m2 mol−1 . The value of x is

Q57.For the given first order reaction A →B the half life of the reaction is 0 . 3010 min. The ratio of the initial concentration of reactant to the concentration of reactant at time 2 . 0 min will be equal to _____. (Nearest integer)

Q57.The limiting molar conductivities of NaI, NaNO3 and AgNO3 are 12. 7, 12. 0 and 13. 3 mSm2 mol−1 , respectively (all at 25 °C ). The limiting molar conductivity of AgI at this temperature is____ mSm2 mol−1 .

Q57.A solution containing 2. 5 × 10−3 kg of a solute dissolved in 75 × 10−3 kg of water boils at 373. 535 K. The molar mass of the solute is mol−1⋅ [nearest integer] (Given : Kb(H2O) = 0. 52 K kg mol−1 and boiling point of water = 373. 15 K)

Q57.PCl5 + H2O →A + HCl A + H2O →B + HCl Find number of ionisable hydrogen in B

Q57.Metal M crystallizes into a FCC lattice with the edge length of 4. 0 × 10−8 cm. The atomic mass of the metal is g/ mol. (Use : NA = 6. 02 × 1023 mol−1 , density of metal, M = 9. 03 g cm−3 )

Q57.The cell potential for the following cell Pt|H2(g)|H+(aq) Cu2+(0 .01 M) Cu(s) is 0. 576 V at 298 K . The pH of the solution is (Nearest integer) (Given : Eo = 0. 34 V and 2.303F RT = 0. 06 V ) Cu2+ / Cu

Q57.The activation energy of one of the reactions in a biochemical process is 532611 J mol−1 . When the temperature falls from 310 K to 300 K , the change in rate constant observed is k300 = x × 10−3k310° . The value of x is [Given: ln 10 = 2. 3 R = 8. 3 J K−1 mol−1 ]

Q58.(a) CoCl3. 4 NH3 , (b) CoCl3 ⋅5 NH3 , (c) CoCl3 ⋅6 NH3 and (d) CoCl (NO3)2 ⋅5 NH3 Number of complex(es) which will exist in cis-trans form is/are

Q58.The rate constants for decomposition of acetaldehyde have been measured over the temperature range 700 −1000 K . The data has been analysed by plotting lnk vs 103T graph. The value of activation energy for the reaction is kJmol−1 . (Nearest integer) (Given : R = 8. 31 JK−1 mol−1 )

Q58.Among Co3 + , Ti2 + , V2 + and Cr2 + ions, one if used as a reagent cannot liberate H2 from dilute mineral acid solution, its spin-only magnetic moment in gaseous state is _____ B.M. (Nearest integer) JEE Main 2022 (25 Jul Shift 1) JEE Main Previous Year Paper