Practice Questions

Q58.The reaction 2 A + B2 →2 AB is an elementary reaction. For a certain quantity of reactants, if the volume of the reaction vessel is reduced by a factor of 3, the rate of the reaction increases by a factor of _____ . (Round off to the Nearest Integer). JEE Main 2021 (17 Mar Shift 2) JEE Main Previous Year Paper

Q58.The rate constant of a reaction increases by five times on increase in temperature from 27°C to 52°C. The value of activation energy in kJmol−1 is ___ .(Rounded-off to the nearest integer) [R = 8. 314 J K−1 mol−1]

Q58.The resistance of conductivity cell with cell constant 1. 14 cm−1 , containing 0. 001M KCl at 298 K is 1500Ω . The molar conductivity of 0. 001M KCl solution at 298 K in S cm2 mol−1 is (Integer answer)

Q58.The spin-only magnetic moment value for the complex [Co(CN)6]4− is...... BM. (nearest integer value) [At. no. of Co = 27]

Q58.A reaction has a half life of 1 min . The time required for 99. 9% completion of the reaction is ___ min. (Round off to the Nearest integer) [Use : ln 2 = 0. 69, ln 10 = 2. 3 ]

Q58.For the galvanic cell, Zn(s) + Cu2+(0. 02M) →Zn2+(0. 04M) + Cu(s) Ecell = … × 10−2 V (Nearest integer) : E0 Cu / Cu2+ = −0. 34 V, EZn / Zn2+ = +0. 76 V, 2.303F RT = 0. 059 V] [Use

Q58. Emf of the following cell at 298 K in V is x × 10−2 Zn Zn2+(0. 1M) Ag+(0. 01M) Ag The value of x is ________________ (Rounded off to the nearest integer) : Eθ = −0. 76 V; Eθ Ag+ / Ag [Given = +0. 80 V; 2.303F RT = 0. 059] Zn2+ / Zn

Q58.If the conductivity of mercury at 0°C is 1 . 07 × 106 S m-1 and the resistance of a cell containing mercury is 0 . 243𝛺, then the cell constant of the cell is 𝑥× 104 m-1 . The value of 𝑥 is ______ . (Nearest integer)

Q58.The conductivity of a weak acid HA of concentration 0. 001 mol L−1 is 2. 0 × 10−5 S cm−1 . If Λ0m(HA) = 190 S cm2 mol−1, the ionization constant (Ka) of HA is equal to ____ ×10−6 (Round off to the Nearest Integer)

Q58. AB2 is 10% dissociated in water to A2+ and B− . The boiling point of 10. 0 molal aqueous solution of AB2 is-- ∘C. (Round off to the Nearest Integer). [Given : Molal elevation constant of water Kb = 0. 5 K kg mol−1 boiling point of pure water = 100°C]

Q58.For the cell Cu(s) Cu2+(aq)(0. 1M)∥Ag+(aq)(0. 01M) Ag(s) the cell potential E1 = 0. 3095 V . For the cell Cu(s) Cu2+(aq)(0. 01M)∥Ag+(aq)(0. 001M) Ag(s) the cell potential = x × 10−2 V. Find value of x (Round off the Nearest Integer). [ Use : 2.303F RT = 0. 059 J ]

Q58.Assume a cell with the following reaction Cu(s) + 2 Ag+(1 × 10−3M) →Cu2+(0. 250M) E∘cell = 2. 97 V JEE Main 2021 (22 Jul Shift 1) JEE Main Previous Year Paper Ecell for the above reaction is V. (Nearest integer) [ Given : log 2. 5 = 0. 3979, T = 298 K]

Q58.The following data was obtained for chemical reaction given below at 975 K. 2 NO(g) + 2H2( g) →N2( g) + 2H2O(g) JEE Main 2021 (26 Aug Shift 1) JEE Main Previous Year Paper [NO] [H2] Rate mol L−1 mol L−1 molL−1 s−1 (A) 8 × 10−5 8 × 10−5 7 × 10−9 (B) 24 × 10−5 8 × 10−5 2. 1 × 10−8 (C) 24 × 10−5 32 × 10−5 8. 4 × 10−8 The order of the reaction with respect to NO_____ is [Integer answer]

Q58.Sucrose hydrolyses in acid solution into glucose and fructose following first order rate law with a half-life of 3. 33 h at 25°C. After 9 h, the fraction of sucrose remaining is f. The value of log10( 1f ) is ________ ×10−2. (Rounded off to the nearest integer) [Assume: In 10 = 2. 303, ln 2 = 0. 693]

Q58.When 3. 00 g of a substance X ' is dissolved in 100 g of CCl4 , it raises the boiling point by 0. 60 K. The molar mass of the substance ' X′ is ___ g mol−1 . (Nearest integer). [Given Kb for CCl4 is 5. 0 K kg mol−1]

Q58.A 5. 0 m mol dm−3 aqueous solution of KCl has a conductance of 0. 55 mS when measured in a cell constant 1. 3 cm−1 . The molar conductivity of this solution is _______ mSm2 mol−1 . (Round off to the Nearest Integer)

Q59. CO2 gas adsorbs on charcoal following Freundlich adsorption isotherm. For a given amount of charcoal, the mass of CO2 adsorbed becomes 64 times when the pressure of CO2 is doubled. The value of n in the Freundlich isotherm equation is ____ ×102. (Round off to the Nearest Integer)

Q59. A and B decompose via first order kinetics with half-lives 54. 0 min and 18. 0 min respectively. Starting from an equimolar non-reactive mixture of A and B, the time taken for the concentration of A to become 16 times that of B is ______ min. (Round off to the Nearest Integer). Q60. [Ti (H2O)6]3+ absorbs light of wavelength 498 nm during a d −d transition. The octahedral splitting energy for the above complex is _______ ×10−19 J. (Round off to the Nearest Integer). h = 6. 626 × 10−34 Js; c = 3 × 108 ms−1 .

Q59. N2O5( g) →2 NO2( g) + 12 O2( g) In the above first order reaction the initial concentration of N2O5 is 2. 40 × 10−2 mol L−1 at 318 K. The concentration of N2O5 after 1 hour was 1. 60×10−2 mol L−1. The rate constant of the reaction at 318 K is ×10−3 min−1 (Nearest integer): [ Given : log 3 = 0. 477, log 5 = 0. 699]

Q59.The total number of unpaired electrons present in the complex K3[Cr(oxalate)3] is______.

Q59.For the first order reaction A →2 B, 1 mole of reactant A gives 0. 2 moles of B after 100 minutes. The half life of the reaction is ...... min. (Round off to the nearest integer). [Use : ln 2 = 0. 69, ln 10 = 2. 3 Properties of logarithms : ln xy = y ln x = ln x −ln y] ln( xy ) (Round off to the nearest integer) Q60. 3 moles of metal complex with formula Co(en)2 Cl3 gives 3 moles of silver chloride on treatment with excess of silver nitrate. The secondary valency of Co in the complex is (Round off to the nearest integer)

Q59.For the reaction, aA + bB →cC + dD, the plot of log k v/s 1T is given below: The temperature at which the rate constant of the reaction is 10−4 s−1 is _____ K. (Rounded-off to the nearest integer) [Given : The rat5e constant of the reaction is 10−5 s−1 at 500 K.]

Q59.For a certain first order reaction 32% of the reactant is left after 570 s. The rate constant of this reaction is ×10−3 s−1. (Round off to the Nearest Integer). [Given: log10 2 = 0. 301, ln 10 = 2. 303 ]

Q59.The sum of oxidation states of two silver ions in AgNH32Ag ( CN ) 2 complex is _____ .

Q59.The decomposition of formic acid on gold surface follows first order kinetics. If the rate constant at 300 K is 1. 0 × 10−3 s−1 and the activation energy Ea = 11. 488 kJ mol−1 , the rate constant at 200 K is _________ ×10−5 s−1 . (Round of to the Nearest Integer). (Given R = 8. 314 J mol−1 K−1 )