Practice Questions

Q45.The half-life period of a first-order reaction is 15 minutes. The amount of substance left after one hour will be (1) 1 of the original amount (2) 1 of the original amount. 16 8 (3) 1 of the original amount. (4) 1 of the original amount. 32 4

Q45.Which of the following statements about the depletion of ozone layer is correct? (1) The problem of ozone depletion is less serious at (2) The problem of ozone depletion is more serious poles because NO2 solidifies and is not available at poles because ice crystals in the clouds over for consuming CIO∘ radicals. poles act as catalyst for photochemical reactions involving the decomposition of ozone of Cl∙ and CIO∙ radicals. (3) Freons, chlorofluorocarbons, are inert. (4) Oxides of nitrogen also do not react with ozone Chemically, they do not react with ozone in in stratosphere. stratosphere.

Q45.In the presence of peroxide, HCl and HI do not give anti-Markownikoff's addition of alkenes because: (1) One of the steps is endothermic in HCl and HI (2) Both HCl and HI are strong acids (3) HCl is oxidizing and the HI is reducing (4) All the steps are exothermic is HCl and HI

Q46.The metal that cannot be obtained by the electrolysis of an aqueous solution of its salt is (1) Ag (2) Ca (3) Cu (4) Cr

Q46.Choose the correct statement with respect to the vapour pressure of a liquid among the following : (1) Increases non-linearly with increasing (2) Decreases non-linearly with increasing temperature temperature (3) Decreases linearly with increasing temperature (4) Increases linearly with increasing temperature

Q46.Global warming is due to increase of: (1) methane and nitrous oxide in atmosphere (2) methane and CO2 in atmosphere (3) methane and O3 in atmosphere (4) methane and CO in atmosphere

Q46.The form of iron obtained from blast furnace is : (1) Cast Iron (2) Wrought Iron (3) Steel (4) Pig Iron

Q46.The appearance of colour in solid alkali metal halides is generally due to: (1) Schottky defect (2) Frenkel defect (3) Interstitial position (4) F-centres

Q47.For the reaction, 3A + 2B →C + D, the differential rate law can be written as : (1) + 31 d[A]dt = −d[C]dt = k[A]n[B]m (2) 13 d[A]dt = d[C]dt = k[A]n[B]m (3) −13 d[A]dt = d[C]dt = k[A]n[B]m (4) −d[A]dt = d[C]dt = k[A]n[B]m

Q47.Given below are the half - cell reactions : Mn2+ + 2e−→Mn ; E∘= −1.18 V 2(Mn3+ + e−→Mn2+) ; E∘= +1.51 V The E∘ for 3Mn2+ →Mn + 2Mn3+ will be : (1) −2.69 V ; the reaction will not occur (2) −2.69 V ; the reaction will occur (3) −0.33 V ; the reaction will not occur (4) −0.33 V ; the reaction will occur

Q47.The gas evolved on heating CaF2 and SiO2 with concentrated H2 SO4 , on hydrolysis gives a white gelatinous precipitate. The precipitate is: (1) Silicic acid (2) Calcium fluorosilicate (3) Hydrofluorosilicic acid (4) Silica gel

Q47.In a monoclinic unit cell, the relation of sides and angles are respectively: (1) a = b ≠c and α = β = γ = 90∘ (2) a ≠ b ≠ c and α = β = γ = 90∘ (3) a ≠b ≠c and β = γ = 90∘≠α (4) a ≠b ≠c and α ≠β ≠γ ≠90∘

Q47.In some solutions, the concentration of H3O+ remains constant even when small amounts of strong acid or strong base are added to them. These solutions are known as: (1) Ideal solutions (2) Colloidal solutions (3) True solutions (4) Buffer solutions

Q48.How many electrons would be required to deposit 6.35 g of copper at the cathode during the electrolysis of an aqueous solution of copper sulphate? (Atomic mass of copper = 63.5u, NA = Avogadro's constant): (1) NA (2) NA 20 10 (3) NA (4) NA 5 2

Q48.Which one of the following ores is known as Malachite: (1) Cu2 S (2) Cu2 O (3) Cu (OH)2. CuCO3 (4) CuFeS2

Q48.For the non-stoichiometry reaction, 2A + B →C + D, the following kinetic data were obtained in three separate experiments, all at 298 K. Initial Concentration Initial Concentration Initial rate of formation of C (A) (B) (mol L−S−) 0.1 M 0.1 M 1.2 × 10−3 0.1 M 0.2 M 1.2 × 10−3 0.2 M 0.1 M 2.4 × 10−3 The rate law for the formation of C is (1) dc dt = k[A][B] (2) dcdt = k[A]2[B] (3) dc dt = k[A][B]2 (4) dcdt = k[A]

Q48.Which of the following is not formed when H2S reacts with acidic K2Cr2O7 solution ? (1) K2SO4 (2) Cr2(SO4)3 (3) S (4) CrSO4

Q48.Given Fe3+(aq) + e−→Fe2+(aq); E0 = +0.77 V Al3+(aq) + 3e−→Al(s); E0 = −1.66 V Br2(aq) + 2e−→2Br−; E0 = +1.09 V Considering the electrode potentials, which of the following represents the correct order of reducing power? JEE Main 2014 (11 Apr Online) JEE Main Previous Year Paper (1) Fe2+ < Al < Br− (2) Br−< Fe2+ < Al (3) Al < Br−< Fe2+ (4) Al < Fe2+ < Br−

Q49.The correct statement about the magnetic properties of [Fe(CN)6]3- and [FeF6]3- is : (Z = 26). (1) Both are paramagnetic. (2) Both are diamagnetic. (3) [Fe(CN)6]3- is paramagnetic, (4) [Fe(CN)6]3- is diamagnetic, [FeF6]3- is diamagnetic. [FeF6]3- is paramagnetic.

Q49.An octahedral complex with molecular composition M.5NH3.Cl.SO4 has two isomers, A and B. The solution of A gives a white precipitate with AgNO3 solution and the solution of B gives white precipitate with BaCl2 solution .The type of isomerism exhibited by the complex is : JEE Main 2014 (19 Apr Online) JEE Main Previous Year Paper (1) Coordinate isomerism (2) Geometrical isomerism (3) Ionisation isomerism (4) Linkage isomerism

Q49.In the reaction of formation of sulphur trioxide by contact process 2SO2 + O2 ⇌2SO3 the rate of reaction was measured as d[O2] dt = −2.5 × 10−4 mol L−1 s−1 . The rate of reaction is terms of [SO2] in molL−1 s−1 will be: (1) −1.25 × 10−4 (2) −2.50 × 10−4 (3) −3.75 × 10−4 (4) −5.00 × 10−4

Q49.The rate coefficient (k) for a particular reactions is 1.3 × 10−4M−1 s−1 at 100∘C, and 1.3 × 10−3 M−1 s−1 at 150∘C. What is the energy of activation (EA) (in kJ) for this reaction? (R = molar gas constant = 8.314JK−1 mol−1 ) (1) 16 (2) 60 (3) 99 (4) 132

Q49.Which series of reactions correctly represents the chemical relations related to iron and its compound? JEE Main 2014 (06 Apr) JEE Main Previous Year Paper (1) dilute H2SO4 H2 SO4,O2 heat (2) O2, heat dilute H2SO4 heat −−−−−−Fe → FeSO4 → Fe2 (SO4)3 → Fe Fe → FeO → FeSO4 → Fe (3) Cl2, heat heat, air Zn (4) O2, heat CO, 600℃ CO, 700℃−−−−−Fe → FeCl3 → FeCl2 →Fe Fe → Fe3 O4 → FeO → Fe

Q50.Nickel (Z = 28) combines with a uninegative monodentate ligand to form a diamagnetic complex [NiL4]2−. The hybridisation involved and the number of unpaired electrons present in the complex are respectively: (1) dsp2, zero (2) sp3, zero (3) dsp2,, one (4) sp3, two

Q50.A compound of vanadium chloride has spin only magnetic moment of 1. 73 BM. Its formula is (1) VCl2 (2) VCl5 (3) VCl4 (4) VCl3