Practice Questions

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 kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is equal to h2 . The value of x ma20 10 x is ( a0 is radius of Bohr's orbit) (Nearest integer) [Given: π = 3. 14]

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)

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

Q58.CO2 gas is bubbled through water during a soft drink manufacturing process at 298 K. If CO2 exerts a partial pressure of 0 . 835 bar then x m mol of CO2 would dissolve in 0 . 9 L of water. The value of x is _______. (Nearest integer) (Henry's law constant for CO2 at 298 K is 1 . 67 × 103 bar)

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.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. PCl5(g) →PCl3(g) + Cl2(g) In the above first order reaction the concentration of PCl5 reduces from initial concentration 50 mol L−1 to 10 mol L−1 in 120 minutes at 300 K. The rate constant for the reaction at 300 K is x × 10−2 min−1. The value of x is __________. [Given log 5 = 0. 6989 ]

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.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)

Q59.The number of halogen/(s) forming halic (V) acid is __________ .

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.To synthesise 1 mole of 2−methylpropan −2−ol from Ethylethanoate equivalents of CH3 MgBr reagent will be required. (Integer value)

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 first order rate constant for the decomposition of CaCO3 at 700 K is 6. 36 × 10−3 s−1 and activation energy is 209 kJ mol−1 . Its rate constant (in s−1) at 600 K is x × 10−6 . The value of x is (Nearest integer) [Given R = 8. 31 J K−1 mol−1; log 6. 36 × 10−3 = −2. 19, 10−4.79 = 1. 62 × 10−5]

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.For coagulation of 50 mL of a sol, 10 mL of 0.5M Cl- ion solution is required. What is the coagulating value of Cl− ion solution (Nearest integer) NOTE: NTA question has been changed because it had errors.}

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.If the activation energy of a reaction is 80. 9 kJ mol−1 , the fraction of molecules at 700 K, having enough energy to react to form products is e−x . The value of x is (Rounded off to the nearest integer) [Use R = 8. 31 J K−1 mol−1 ]

Q59.The overall stability constant of the complex ion [Cu (NH3)4]2+ is 2. 1 × 1013. The overall dissociation constant is y × 10−14 . Then y is (Nearest integer)

Q59.In Carius method for estimation of halogens, 0. 2 g of an organic compound gave 0. 188 g of AgBr. The percentage of bromine in the compound is __________. (Nearest integer) [Atomic mass: Ag = 108, Br = 80 ] Q60. 1 mol of an octahedral metal complex with formula MCl3 ⋅2 L on reaction with excess of AgNO3 gives 1 mol of AgCl. The denticity of Ligand L is___________ (Integer answer)