Practice Questions

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.When 9 . 45 g of ClCH2COOH is added to 500 mL of water, its freezing point drops by 0 . 5°C . The dissociation constant of ClCH2COOH is 𝑥× 10-3 . The value of x is off to the nearest integer) KfH2O = 1 . 86 K kg mol-1

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)

Q59.Among the following allotropic forms of sulphur, the number of allotropic forms, which will show paramagnetism is _______. (A) α -sulphur (B) β -sulphur (C) S2 -form JEE Main 2021 (24 Feb Shift 2) JEE Main Previous Year Paper

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 spin only magnetic moment of a divalent ion in aqueous solution (atomic number 29) is ___ BM.

Q59.Consider the cell at 25°C ZnZn2 + aq, 1 M‖Fe3 + (aq), Fe2 + aqPts The fraction of total iron present as Fe3 + ion at the cell potential of 1 . 500 V is x × 10-2. The value of x is ______. (Nearest integer) Given: E∘ + + = 0 . 77V, E∘ + = - 0 . 76V Fe3 | Fe2 Zn2 | Zn

Q59.The sum of oxidation states of two silver ions in AgNH32Ag ( CN ) 2 complex 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 a chemical reaction A →B , it was found that concentration of B is increased by 0. 2 mol L−1 in 30 min. The average rate of the reaction is ________ ×10−1 mol L−1 h−1 . (in nearest integer)

Q59.A xenon compound A upon partial hydrolysis gives XeO2 F2 . The number of lone pair of electrons present in compound A is ___ (Round off to the Nearest integer)

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 )

Q59.CH4 is adsorbed on 1 g charcoal at 0°C following the Freundlich adsorption isotherm. 10 . 0 mL of CH4 is adsorbed at 100 mm of Hg, whereas 15 . 0 mL is adsorbed at 200 mm of Hg . The volume of CH4 adsorbed at 300 mm of Hg is 10x mL . The value of x is _________ × 10-2 . (Nearest integer) [Use log102 = 0 . 3010, log103 = 0 . 4771]

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

Q59.The number of 4f electrons in the ground state electronic configuration of Gd2+ is [Atomic number of Gd = 64]

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. 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.In the ground state of atomic Fe(Z = 26), the spin-only magnetic moment is ×10−1 BM. (Round off to the Nearest Integer). [ Given : √3 = 1. 73, √2 = 1. 41]

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

Q59.To synthesise 1 mole of 2−methylpropan −2−ol from Ethylethanoate equivalents of CH3 MgBr reagent will be required. (Integer value)

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)

Q60.The total number of negative charge in the tetrapeptide, Gly-Glu-Asp-Tyr, at pH 12. 5 will be_______ (Integer answer)

Q60.The total number of reagents from those given below, that can convert nitrobenzene into aniline is __________ . (Integer answer) I. Sn −HCl II. Sn −NH4 OH JEE Main 2021 (31 Aug Shift 1) JEE Main Previous Year Paper III. Fe −HCl IV. Zn −HCl V. H2 −Pd VI. H2− Raney Nickel

Q60.In the electrolytic refining of blister copper, the total number of main impurities, from the following, removed as anode mud is ___________ . Pb, Sb, Se, Te, Ru, Ag, Au and Pt

Q60.A metal surface is exposed to 500 nm radiation. The threshold frequency of the metal for photoelectric current is 4. 3 × 1014 Hz . The velocity of ejected electron is ___ × 105 ms−1 (Nearest integer) [Use : h = 6. 63 × 10−34 Js, me = 9. 0 × 10−31 kg] p and q are roots of the equation : + = + i)100 299(p iq), then