Practice Questions

Q48.The standard reduction potentials at 295 K for the following half cells are given below: NO3−+ 4H+ + 3e−→NO(g) + 2H2O Eo = 0. 97 V V2+(aq) + 2e−→V(s) Eo = −1. 19 V Fe3+(aq) + 3e−→Fe(s) Eo = −0. 04 V Ag+(aq) + e−→Ag(s) Eo = 0. 80 V Au3+(aq) + 3e−→Au(s) Eo = 1. 40 V The number of metal(s) which will be oxidised by NO3− in aqueous solution is _____.

Q48.The number of statement/s which are the characteristics of physisorption is ___________. A. It is highly specific in nature B. Enthalpy of adsorption is high C. It decreases with increase in temperature D. It results into unimolecular layer E. No activation energy is needed

Q49.The graph of log mx vs log p for an adsorption process is a straight line inclined at an angle of 45° with intercept equal to 0. 6020 . The mass of gas adsorbed per unit mass of adsorbent at the pressure of 0. 4 atm is JEE Main 2023 (30 Jan Shift 2) JEE Main Previous Year Paper _____ ×10−1 (Nearest integer) Given : log 2 = 0. 3010

Q49.Total number of acidic oxides among N2O3, NO2, N2O, Cl2 O7, SO2, CO, CaO, Na2 O and NO is _____ .

Q49.The number of correct statements about modern adsorption theory of heterogeneous catalysis from the following is ...... A. The catalyst is diffused over the surface of reactants. B. Reactants are adsorbed on the surface of the catalyst. C. Occurrence of chemical reaction on the catalyst's surface through formation of an intermediate. D. It is a combination of intermediate compound formation theory and the old adsorption theory. E. It explains the action of the catalyst as well as those of catalytic promoters and poisons.

Q49.The rate constant for a first order reaction is 20 min−1 . The time required for the initial concentration of the reactant to reduce to its 1 level is ______ × 10−2 min . (Nearest integer) 32

Q49. A →B The above reaction is of zero order. Half life of this reaction is 50 min . The time taken for the concentration of A to reduce to one-fourth of its initial value is min . (Nearest integer)

Q49.The reaction 2NO + Br2 →2 NOBr takes place through the mechanism given below NO + Br2 ⇌NOBr2 (fast) NOBr2 + NO →2 NOBr (slow) The overall order of the reaction is _____.

Q50.Coagulating value of the electrolytes AlCl3 and NaCl tor As2 S3 are 0. 09 and 50. 04 respectively. The coagulating power of AlCl3 is x times the coagulating power of NaCl. The value of x is

Q50. XeF4 reacts with SbF5 to form [XeFm]n+[SbFy]2− m + n + y + z = ? .

Q50.The number of colloidal systems from the following, which will have 'liquid' as the dispersion medium, is _____. Gem stones, paints, smoke, cheese, milk, hair cream, insecticide sprays, froth, soap lather

Q51.The density of 3M solution of NaCl is 1 . 0 g mL-1. Molality of the solution is ______ × 10-2 m (Nearest integer). Given: Molar mass of Na and Cl is 23 and 35 . 5 g mol-1 respectively.

Q51.The number of bent-shaped molecule/s from the following is ______ N3- , NO2- , I3- , O3, SO2

Q51.On complete combustion, 0 . 492 g of an organic compound gave 0 . 792 g of CO2. The % of carbon in the organic compound is (Nearest integer)

Q51.The number of paramagnetic species from the following is [Ni(CN)4]2−, [Ni(CO)4], [NiCl4]2− [Fe(CN)6]4−, [Cu (NH3)4]2+ [Fe(CN)6]3− and [Fe (H2O)6]2+

Q51. The electron in the nth orbit of Li2 + is excited to ( n + 1 ) orbit using the radiation of energy 1 . 47 × 10-17 J (as shown in the diagram). The value of n is ___________ Given : RH = 2 . 18 × 10-18 J

Q52.How many of the following metal ions have similar value of spin only magnetic moment in gaseous state? ________ (Given: Atomic number : V, 23; Cr, 24; Fe, 26; Ni, 28) V3+, Cr3+, Fe2+, Ni3+

Q52.For independent process at 300 K. Process 𝛥H / kJmol-1 𝛥S / JK-1 A -25 -80 B -22 40 C 25 -50 D 22 20 JEE Main 2023 (24 Jan Shift 1) JEE Main Previous Year Paper The number of non-spontaneous process from the following is _____ .

Q52.The wavelength of an electron of kinetic energy 4 . 50 × 10-29 J is ________ × 10 – 5 m . (Nearest integer) Given: mass of electron is9 × 10 – 31 kg, h = 6 . 6 × 10 – 34 Js

Q52.Solid fuel used in rocket is a mixture of Fe2O3 and Al (in ratio 1 : 2). The heat evolved ( kJ ) per gram of the mixture is _____ (Nearest integer) Given ΔHf0Al2O3 = - 1700 kJ mol-1 ΔHf0Fe2O3 = - 840 kJ mol-1 Molar mass of Fe, AI and O are 56, 27 and 16 g mol – 1 respectively

Q52.The ratio of sigma and π bonds present in pyrophosphoric acid is

Q52.Electrons in a cathode ray tube have been emitted with a velocity of 1000 ms-1. The number of following statements which is/are true about the emitted radiation is Given : h = 6 × 10-34Js, me = 9 × 10-31 kg (A ) The deBroglie wavelength of the electron emitted is 666 . 67 nm (B ) The characteristic of electrons emitted depend upon the material of the electrodes of the cathode ray tube. (C) The cathode rays start from cathode and move towards anode. (D ) The nature of the emitted electrons depends on the nature of the gas present in cathode ray tube..

Q52.Zinc reacts with hydrochloric acid to give hydrogen and zinc chloride. The volume of hydrogen gas produced at STP from the reaction of 11 . 5 g of zinc with excess HCl is L (Nearest integer) (Given : Molar mass of Zn is 65 . 4 g mol-1 and Molar volume of H2 at STP = 22 . 7 L )

Q52.The sum of lone pairs present on the central atom of the interhalogen IF5 and IF7 is ______

Q53.Total number of moles of AgCl precipitated on addition of excess of AgNO3 to one mole each of the following complexes [Co (NH3)4 Cl2] Cl, [Ni (H2O)6] Cl2, [Pt (NH3)2 Cl2] and [Pd (NH3)4] Cl2 is