Practice Questions

Q37.The possibility of photochemical smog formation is more at (1) Marshy lands (2) Industrial areas (3) Himalayan villages in winter (4) The places with healthy vegetation JEE Main 2023 (06 Apr Shift 1) JEE Main Previous Year Paper

Q37. Where Nu = Nucleophile Find out the correct statement from the options given below for the above two reactions. JEE Main 2023 (11 Apr Shift 1) JEE Main Previous Year Paper (1) Reaction (I) is of 2nd order and reaction (II) is of (2) Reactions (I) and (II) both are of 2nd order 1st order (3) Reactions (I) is of 1st order and reaction (II) is of (4) Reaction (I) and (II) both are of 1st order 2 nd order

Q37.What is the correct order of acidity of the protons marked 𝐴– 𝐷 in the given compounds? (1) HC > HD > HB > HA (2) HC > HD > HA > HB (3) HD > HC > HB > HA (4) HC > HA > HD > HB

Q37.An indicator ‘ X’ is used for studying the effect of variation in concentration of iodide on the rate of reaction of iodide ion with H2O2 at room temp. The indicator ‘ X’ forms blue colored complex with compound ‘ A’ present in the solution. The indicator ‘ X’ and compound ‘ A’ respectively are (1) Starch and iodine (2) Methyl orange and H2O2 (3) Starch and H2O2 (4) Methyl orange and iodine

Q37.Chlorides of which metal are soluble in organic solvents: (1) Ca (2) Mg (3) K (4) Be JEE Main 2023 (30 Jan Shift 2) JEE Main Previous Year Paper

Q38.Given below are two statements: Statement-I : Methyl orange is a weak acid. Statement-II : The benzenoid form of methyl orange is more intense/deeply coloured than the quinonoid form. In the light of the above statement, choose the most appropriate answer from the options given below: (1) Both Statement-I and Statement-II are incorrect(2) Statement-I is incorrect but Statement-II is correct (3) Both Statement-I and Statement-II are correct (4) Statement-I is correct but Statement-II is incorrect

Q38.In the depression of freezing point experiment A. Vapour pressure of the solution is less than that of pure solvent B. Vapour pressure of the solution is more than that of pure solvent C. Only solute molecules solidify at the freezing point D. Only solvent molecules solidify at the freezing point (1) A and D only (2) B and C only (3) A and C only (4) A only

Q38.The titration curve of weak acid vs. strong base with phenolphthalein as indicator is shown below. The Kphenolphthalein = 4 × 10−10 Given: log 2 = 0. 3 The number of following statement/s which is/are correct about phenolphthalein is _______ A. It can be used as an indicator for the titration of weak acid with weak base. B. It begins to change colour at pH = 8. 4 C. It is a weak organic base D. It is colourless in acidic medium Q39. 2 IO−3 + xI−+ 12H+ →6I2 + 6H2 What is the value of x ? (1) 2 (2) 12 (3) 10 (4) 6

Q38.Which of the given compounds can enhance the efficiency of hydrogen storage tank? (1) Li /P4 (2) SiH4 (3) NaNi5 (4) Di-isobutylaluminium hydride

Q38.The decreasing order of hydride affinity for following carbocations is: (a) (2) (3) (4) Choose the correct answer from the options given below: (1) C, A, D, B (2) C, A, B, D (3) A, C, D, B (4) A, C, B, D

Q38.Which hydride among the following is less stable? (1) BeH2 (2) HF (3) NH3 (4) LiH

Q38.Decreasing order of reactivity towards electrophilic substitution for the following compounds is: (1) d > a > e > c > b (2) e > d > a > b > c (3) a > d > e > b > c (4) c > b > a > d > e

Q38.An analyst wants to convert 1 L HCl of pH = 1 to a solution of HCl of pH = 2. The volume of water needed to do this dilution is _____ mL. (Nearest integer)

Q38.Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Order of acidic nature of the following compounds is A > B > C. Reason R: Fluoro is a stronger electron withdrawing group than Chloro group. In the light of the above statements, choose the correct answer from the options given below : (1) A is false but R is true (2) Both A and R are correct and R is the correct explanation of A (3) A is true but R is false (4) Both A and R are correct but R is NOT the correct explanation of A

Q38.Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Amongst He, Ne, Ar and Kr; 1 g of activated charcoal adsorbs more of Kr. Reason R: The critical volume Vc (cm3 mol – 1 ) and critical pressure Pc (atm) is highest for Krypton but the compressibility factor at critical point Zc is lowest for Krypton. In the light of the above statements, choose the correct answer from the options given below. (1) A is true but R is false (2) A is false but R is true (3) Both A and R are true but R is NOT the correct (4) Both A and R are true and R is the correct explanation of A explanation A

Q38.During the reaction of permanganate with thiosulphate, the change in oxidation of manganese occurs by value of 3. Identify which of the below medium will favour the reaction. (1) Both aqueous acidic and neutral (2) Aqueous neutral (3) Both aqueous acidic and faintly alkaline (4) Aqueous acidic

Q38.The starting material for convenient preparation of deuterated hydrogen peroxide (D2O2) in laboratory is: (1) K2 S2O8 (2) 2-ethylanthraquinol (3) BaO2 (4) BaO

Q38.Which one among the following metals is the weakest reducing agent? (1) K (2) Rb (3) Na (4) Li

Q38.In sulphur estimation. 0. 471 g of an organic compound gave 1. 4439 g of barium sulphate. The percentage of sulphur in the compound is _______(Nearest Integer) (Given: Atomic mass Ba: 137u : S : 32u, O : 16u )

Q38.Adding surfactants in non polar solvent, the micelles structure will look like (a) (b) JEE Main 2023 (31 Jan Shift 1) JEE Main Previous Year Paper (c) (d) (1) b (2) c (3) a (4) d

Q38.At 298 K, the solubility of silver chloride in water is 1. 434 × 10−3 g L−1 . The value of −logKsp for silver chloride is (Given mass of Ag is 107. 9 g mol−1 , and mass of Cl is 35. 5 g mol−1 )

Q38.The major products ‘A’ and ‘B’, respectively, are (1) (2) (3) (4)

Q38.In which of the following reactions the hydrogen peroxide acts as a reducing agent? (1) PbS + 4H2O2 →PbSO4 + 4H2O (2) 2 Fe2+ + H2O2 →2 Fe3+ + 2 OH− (3) HOCl + H2O2 →H3O+ + Cl−1 + O2 (4) Mn2+ + H2O2 →Mn4+ + 2 OH−

Q38. A2 + B2 →2 AB. ΔHf = −200 kJ mol−1 AB, A2 and B2 are diatomic molecules. If the bond enthalpies of A2, B2 and AB are in the ratio 1 : 0. 5 : 1, then the bond enthalpy of A2 is _________kJ mol–1 (Nearest integer) Q39. 25. 0 mL of 0. 050 M Ba (NO3)2 is mixed with 25. 0 mL of 0. 020 M NaF. Ksp of BaF2 is 0. 5 × 10–6 at 298K. The ratio of [Ba2+][F−]2 and Ksp is ______.

Q38.Thin layer chromatography of a mixture shows the following observation: The correct order of elution in the silica gel column chromatography is (1) B, A, C (2) B, C, A (3) A, C, B (4) C, A, B