Practice Questions

Q37.Which among the following is incorrect statement? (1) Electromeric effect dominates over inductive (2) The electromeric effect is, temporary effect effect (3) Hydrogen ion (H+)shows negative electromeric (4) The organic compound shows electromeric effect effect in the presence of the reagent only.

Q37.Given below are two statements: Statement (I) : SiO2 and GeO2 are acidic while SnO and PbO are amphoteric in nature. Statement (II) : Allotropic forms of carbon are due to property of catenation and pπ - dπ bond formation. In the light of the above statements, choose the most appropriate answer from the options given below: (1) Both Statement I and Statement II are false (2) Both Statement I and Statement II are true (3) Statement I is true but Statement II is false (4) Statement I is true but Statement II is true

Q37.The number of neutrons present in the more abundant isotope of boron is ' x '. Amorphous boron upon heating with air forms a product, in which the oxidation state of boron is ' y '. The value of x + y is _______ (1) 3 (2) 9 (3) 4 (4) 6

Q37.Which of the following molecule/species is most stable? (1) (2) (3) (4)

Q38.Identify structure of 2, 3-dibromo-1-phenylpentane. (1) (2) (3) (4)

Q38.Thiosulphate reacts differently with iodine and bromine in the reactions given below: 2 S2O2−3 + I2 →S4O2−6 + 2I− Which of the following statement justifies the above dual S2O2−3 + 5Br2 + 5H2O →2SO2−4 + 4Br−+ 10H+ behaviour of thiosulphate? (1) Bromine is a stronger oxidant than iodine (2) Thiosulphate undergoes oxidation by bromine and reduction by iodine in these reaction (3) Bromine is a weaker oxidant than iodine (4) Bromine undergoes oxidation and iodine undergoes reduction in these reactions

Q38.How can an electrochemical cell be converted into an electrolytic cell? (1) Applying an external opposite potential lower (2) Reversing the flow of ions in salt bridge. than E0 cell. (3) Applying an external opposite potential greater (4) Exchanging the electrodes at anode and cathode. than E0 cell-

Q38.Which among the following has highest boiling point? (1) CH3CH2CH2CH3 (2) CH3CH2CH2CH2 - OH (3) CH3CH2CH2CHO (4) H5C2 - O - C2H5

Q38.Common name of Benzene - 1, 2 - diol is - (1) catechol (2) o-cresol (3) quinol (4) resorcinol

Q38.Match List I with List II LIST I (Technique) LIST II (Application) A. Distillation I. Separation of glycerol from spent-lye B. Fractional distillation II. Aniline - Water mixture C. Steam distillation III. Separation of crude oil fractions D. Distillation under reduced pressure IV. Chloroform-Aniline Choose the correct answer from the options given below: (1) A-IV, B-I, C-II, D-III (2) A-IV, B-III, C-II. D-I (3) A-I. B-II, C-IV, D-III (4) A-II, B-III. C-I, D-IV

Q38. List - I List - II (Pair of compounds) (Isomerism) (A) n-propanol and Isopropanol (I) Metamerism Match List I with List II Choose the (B) Methoxypropane and ethoxyethane (II) Chain Isomerism (C) Propanone and propanal (III) Position Isomerism (D) Neopentane and Isopentane (IV) Functional Isomerism correct answer from the options given below : (1) (A)-(II), (B)-(I), (C)-(IV), (D)-(III) (2) (A)-(III), (B)-(I), (C)-(II), (D)-(IV) (3) (A)-(I), (B)-(III), (C)-(IV), (D)-(II) (4) (A)-(III), (B)-(I), (C)-(IV), (D)-(II)

Q38.Compound A formed in the following reaction reacts with B gives the product C. Find out A and B. (1) A = CH3 −C ≡C−Na+, B = CH3 −CH2 −CH2 −Br (2) A = CH3 −CH = CH2, B = CH3 −CH2 −CH2 −Br (3) A = CH3 −CH2 −CH3, B = CH3 −C ≡CH (4) A = CH3 −C ≡C−Na+, B = CH3 −CH2 −CH3

Q38.The correct stability order of the following resonance structures of CH3 −CH = CH −CHO is (1) I > II > III (2) II > III > I (3) II > I > III (4) III > II > I

Q38.Functional group present in sulphonic acids is : (1) −SO4H (2) −SO3H (3) (4) −SO2 JEE Main 2024 (06 Apr Shift 1) JEE Main Previous Year Paper

Q38.Chromatographic technique/s based on the principle of differential adsorption is/are A. Column chromatography B. Thin layer chromatography C. Paper chromatography Choose the most appropriate answer from the options given below: (1) B only (2) A only (3) A & B only (4) C only

Q38.Number of σ and π bonds present in ethylene molecule is respectively : (1) 4 and 1 (2) 5 and 2 (3) 3 and 1 (4) 5 and 1

Q38.Given below are two statements : Statement (I) : Potassium hydrogen phthalate is a primary standard for standardisation of sodium hydroxide solution. Statement (II) : In this titration phenolphthalein can be used as indicator. In the light of the above statements, choose the most appropriate answer from the options given below: (1) Both Statement I and Statement II are correct (2) Statement I is correct but Statement II is incorrect (3) Statement I is incorrect but Statement II is (4) Both Statement I and Statement II are incorrect correct

Q38.Given below are two statements : Statement (I) : Kjeldahl method is applicable to estimate nitrogen in pyridine. Statement (II) : The nitrogen present in pyridine can easily be converted into ammonium sulphate in Kjeldahl method. In the light of the above statements, choose the correct answer from the options given below (1) Both Statement I and Statement II are true (2) Both Statement I and Statement II are false (3) Statement I is false but Statement II is true (4) Statement I is true but Statement II is false

Q38.Relative stability of the contributing structures is : (1) (I) > (II) > (III) (2) (I) > (III) > (II) (3) (II) > (I) > (III) (4) (III) > (II) > (I)

Q38.If a substance '𝐴' dissolves in solution of a mixture of ' 𝐵' and ' 𝐶 ' with their respective number of moles as 𝑛𝐴, 𝑛𝐵 and 𝑛𝐶, mole fraction of 𝐶 in the solution is: JEE Main 2024 (30 Jan Shift 2) JEE Main Previous Year Paper nC nC (1) (2) nA × nB × nC nA + nB + nC (3) nC (4) nB nA - nB - nC nA + nB

Q38. Cyclohexene is _________ type of an organic compound. (1) Benzenoid aromatic (2) Benzenoid non-aromatic (3) Acyclic (4) Alicyclic

Q38.The quantity which changes with temperature is: (1) Molarity (2) Mass percentage (3) Molality (4) Mole fraction

Q38. Identify (B) and (C) and how are (A) and (C) related ? (1) (2) (3) (4)

Q38.The difference in energy between the actual structure and the lowest energy resonance structure for the given compound is: (1) electromeric energy (2) resonance energy (3) ionization energy (4) hyperconjugation energy JEE Main 2024 (29 Jan Shift 1) JEE Main Previous Year Paper

Q39.The fragrance of flowers is due to the presence of some steam volatile organic compounds called essential oils. These are generally insoluble in water at room temperature but are miscible with water vapour in the vapour phase. A suitable method for the extraction of these oils from the flowers is: (1) crystallisation (2) distillation under reduced pressure (3) distillation (4) steam distillation