Practice Questions

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.In alkaline medium, the reduction of permanganate anion involves a gain of ____________ electrons.

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

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

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.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.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

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

Q57.Sodium metal crystallises in a body centred cubic lattice with unit cell edge length of 4 Å. The radius of sodium atom is ___ × 10-1Å. (Nearest integer)

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.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.The logarithm of equilibrium constant for the reaction Pd2 + + 4Cl- ⇌PdCl42 - is (Nearest integer) 2 . 303RT Given: = 0 . 06 V F Pd2 + + 2e- ⇌Pd(s) E𝑜= 0 . 83 V ( aq ) PdCl42 - (aq) + 2e- ⇌Pd(s) + 4Cl- (aq) Eo = 0 . 65 V

Q57.The mass of NH3 produced when 131. 8 kg of cyclohexane carbaldehyde undergoes Tollen’s test is _____ kg. (Nearest Integer) Molar mass of C = 12 g/ mol N = 14 g/ mol O = 16 g/ mol

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.At 298 K, a 1 litre solution containing 10 mmol of Cr2O72 - and 100mmol of Cr3 + shows a pH of 3 . 0. 2 - + 2 . 303RT Given : Cr2O7 →Cr3 ; E0 = 1 . 330 V and F = 0 . 059 V The potential for the half cell reaction is x × 10-3 V . The value of x is _____ .

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.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.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.Consider the cell PtsH2g, 1atmH+aq, 1M | Fe3 + aq, Fe2 + aq Pt s When the potential of the cell is 0 . 712 V at 298 K, the ratio Fe2 + / Fe3 + is (Nearest integer) + + + + 2 . 303RT Given: Fe3 + e- = Fe2 , E°Fe3 , Fe2 Pt = 0 . 771 = 0 . 06 V F

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

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

Q58.If the degree of dissociation of aqueous solution of weak monobasic acid is determined to be 0 . 3, then the observed freezing point will be _____ % higher than the expected/theoretical freezing point. (Nearest integer).

Q58.Among the following, the number of tranquilizer/s is/are A. Chloroliazepoxide B. Veronal C. Valium D. Salvarsan

Q58.In Chromyl chloride, the oxidation state of chromium is (+) ___________.

Q58.The number of correct statement/s from the following is _____ . A.Larger the activation energy, smaller is the value of the rate constant. B. The higher is the activation energy, higher is the value of the temperature coefficient. C. At lower temperatures, increase in temperature causes more change in the value of k than at higher temperature. D. A plot of ln k vs 1 is a straight line with slope equal to -Ea T R