Practice Questions

Q56. The number of molecules which gives haloform test among the following molecules is :

Q56.The major product formed in the following reaction is (1) (2) (3) (4) Q57.. Match List I with List II : List II (Compound with Functional group List I (Reagents used) detected) A.Alkaline solution of copper I. sulphate and sodium citrate B. Neutral FeCl3 solution II. C. Alkaline chloroform solution III. D.Potassium iodide and sodium IV hypochloride Choose the correct answer from the options given below : JEE Main 2023 (08 Apr Shift 1) JEE Main Previous Year Paper (1) A-III, B-IV, C-I, D-II (2) A-III, B-IV, C-II, D-I (3) A-IV, B-I, C-II, D-III (4) A-II, B-IV, C-III, D–I

Q56.Among the following the number of compounds which will give positive iodoform reaction is _____. (a) 1 -Phenylbutan- 2 -one (b) 2-Methylbutan- 2-ol (c) 3-Methylbutan- 2-ol (d) 1-Phenylethanol (e) 3, 3 -dimethylbutan- 2-one (f) 1-Phenylpropan- 2-ol

Q56.The number of correct statement/s involving equilibria in physical processes from the following is ________ (A) Equilibrium is possible only in a closed system at a given temperature. (B) Both the opposing processes occur at the same rate. (C) When equilibrium is attained at a given temperature, the value of all its parameters became equal (D) For dissolution of solids in liquids, the solubility is constant at a given temperature.

Q56. The value of x in compound ‘ D’ is _____

Q56.Decreasing order towards SN1 reaction for the following compounds is: (1) a > c > d > b (2) a > b > c > d (3) b > d > c > a (4) d > b > c > a

Q56.Number of bromo derivatives obtained on treating ethane with excess of Br2 in diffused sunlight is _________

Q56.For a reversible reaction A ⇌B, the ΔH forward reaction = 20 kJ mol–1 . The activation energy of the uncatalyzed forward reaction is 300 kJ mol–1 . When the reaction is catalysed keeping the reactant concentration same, the rate of the catalysed forward reaction at 27∘C is found to be same as that of the uncatalyzed reaction at 327∘C. The activation energy of the catalysed backward reaction is _______ kJ mol–1 . Q57. 20 mL of 0. 5 M NaCl is required to coagulate 200 mL of As2 S3 solution in 2 hours. The coagulating value of NaCl is ___________.

Q56.Given below are two statements : Statement I : Pure Aniline and other arylamines are usually colourless. Statement II : Arylamines get coloured on storage due to atmospheric reduction. 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 incorrect (2) Both Statement I and Statement II are correct (3) Statement I is correct but Statement II is (4) Statement I is incorrect but Statement II is incorrect correct

Q56.At 27°C, a solution containing 2 . 5 g of solute in 250 . 0 mL of solution exerts an osmotic pressure of 400 Pa. The molar mass of the solute is g mol-1 (Nearest integer) (Given : R = 0 . 083 L bar -1 mol-1 )

Q56.Some amount of dichloromethane CH2Cl2 is added to 671 . 141mL of chloroform CHCl3 to prepare 2 . 6 × 10-3M solution of CH2Cl2DCM. The concentration of DCM is _____ ppm (by mass). JEE Main 2023 (30 Jan Shift 1) JEE Main Previous Year Paper Given: Atomic mass : C = 12; H: 1; Cl = 35 . 5 density of CHCl3 = 1 . 49g cm-3

Q57.Which of the following statements is incorrect for antibiotics? (1) An antibiotic must be a product of metabolism. (2) An antibiotic is a synthetic substance produced as a structural analogue of naturally occurring antibiotic. (3) An antibiotic should promote the growth or (4) An antibiotic should be effective in low survival of microorganisms. concentrations.

Q57.Mass of Urea NH2CONH2 required to be dissolved in 1000 g of water in order to reduce the vapour pressure of water by 25% is _______ g . (Nearest integer) Given : Molar mass of N, C, O and H are 14, 12, 16 and 1 g mol-1 respectively.

Q57. Product [X] formed in the above reaction is: (1) (2) (3) (4)

Q57.In an electrochemical reaction of lead, at standard temperature, if EPb2o + / Pb = n Volt, then the value of E°Pb2 + / Pb4 + is given by m – xn. The value of x is _______. EPb4o + / Pb (Nearest integer)

Q57.Number of compounds giving (i) red colouration with ceric ammonium nitrate and also (ii) positive iodoform test from the following is _________ JEE Main 2023 (25 Jan Shift 2) JEE Main Previous Year Paper

Q57.An aqueous solution of volume 300 cm3 contains 0 . 63 g of protein. The osmotic pressure of the solution at 300 K is 1 . 29 mbar. The molar mass of the protein is gmol-1. Given : R = 0 . 083 LbarK-1 mol-1

Q57.At what pH, given half cell MnO4- (0 . 1M) ∣Mn2 + ( 0 . 001 M ) will have electrode potential of 1 . 282 V ? (Nearest Integer) Given 𝑜 + = 1 . 54 V, 2 . 303RT = 0 . 059 V EMnO4- / Mn2 F

Q57.In the following reaction, the total number of oxygen atoms in 𝑋 and 𝑌 is______ Na2O + H2O →2X Cl2O7 + H2O →2Y

Q57.A compound ′X′ when treated with phthalic anhydride in presence of concentrated H2 SO4 yields ′Y′. ′Y′ is used as an acid/base indicator. ′X′ and ′Y′ are respectively (1) Anisole, methyl orange (2) Salicylaldehyde, Phenolphthalein (3) Toludine, Phenolphthalein (4) Carbolic acid, Phenolphthalein

Q57.For the given reaction The, total number of possible products formed by tertiary carbocation of A is _______. JEE Main 2023 (13 Apr Shift 1) JEE Main Previous Year Paper

Q57.Number of isomeric aromatic amines with molecular formula C8H11N, which can be synthesized by Gabriel Phthalimide synthesis is _____.

Q57.Choose the correct colour of the product for the following reaction. (1) Yellow (2) White (3) Red (4) Blue

Q57. In the above conversion of compound ( X ) to product ( Y ), the sequence of reagents to be used will be: (1) (i) Br2, Fe (2) (i) Br2(aq) (ii) Fe, H+ (ii) LiAlH4 (iii) LiAlH4 (iii) H3O+ (3) (i) Fe, H+ (4) (i) Fe, H+ (ii) Br2(aq) (ii) Br2(aq) (iii) HNO2 (iii) HNO2 (iv) CuBr (iv) H3 PO2

Q57.Reaction of propanamide with Br2 / KOH (aq) produces: (1) Ethylnitrile (2) Propylamine (3) Propanenitrile (4) Ethylamine