Practice Questions

Q51.Potassium dichromate acts as a strong oxidizing agent in acidic solution. During this process, the oxidation state changes from (1) +3 to +1 (2) +6 to +3 (3) +2 to +1 (4) +6 to +2

Q51.The energy of one mole of photons of radiation of frequency 2 × 1012 Hz in Jmol-1 is _____ . (Nearest integer) (Given: h = 6 . 626 × 10-34Js NA = 6 . 022 × 1023 mol-1)

Q51.A solution of sugar is obtained by mixing 200 g of its 25% solution and 500 g of its 40 % solution (both by mass). The mass percentage of the resulting sugar solution is _______ (Nearest integer) JEE Main 2023 (11 Apr Shift 1) JEE Main Previous Year Paper

Q51.Among following compounds, the number of those present in copper matte is A. CuCO3 B. Cu2 S C. Cu2 O D. FeO

Q51.If wavelength of the first line of the Paschen series of hydrogen atom is 720 nm, then the wavelength of the second line of this series is _______ nm. (Nearest integer)

Q52.When 2 litre of ideal gas expands isothermally into vacuum to a total volume of 6 litre, the change in internal energy is _____ J. (Nearest integer) Q53.600mL of 0 . 01M HCl is mixed with 400mL of 0 . 01M H2SO4. The pH of the mixture is _____ × 10-2. (Nearest integer) [Given log2 = 0 . 30, log3 = 0 . 48, log5 = 0 . 69, log7 = 0 . 84, log11 = 1 . 04]

Q52.The orbital angular momentum of an electron in 3 s orbital is 2π.xh The value of Q53.20 mL of 0 . 1MNaOH is added to 50 mL of 0 . 1M acetic acid solution. The pH of the resulting solution is × 10-2. (Nearest integer) Given : pK𝑎CH3COOH = 4 . 76 log 2 = 0 . 30 log 3 = 0 . 48

Q52.For a metal ion, the calculated magnetic moment is 4 . 90 BM. This metal ion has _______ number of unpaired electrons

Q53.Which element is not present in Nessler’s reagent? (1) Mercury (2) Potassium (3) Iodine (4) Oxygen

Q53.The total change in the oxidation state of manganese involved in the reaction of KMnO4 and potassium iodide in the acidic medium is ________.

Q53.In the cumene to phenol preparation in presence of air, the intermediate is (1) (2) (3) (4)

Q53.The denticity of the ligand present in the Fehling's reagent is _____ .

Q53.Element not present in Nessler’s reagent is (1) N (2) Hg (3) I (4) K

Q53.At constant temperature, a gas is at a pressure of 940 . 3 mm Hg. The pressure at which its volume decreases by 40% is ______ mm Hg. (Nearest integer) +2 . 2 V +0 . 70 V -0 . 45 V 2 - ⟶ Fe3 + ⟶ Fe2 + ⟶ Fe0

Q54.In the following halogenated organic compounds the one with maximum number of chlorine atoms in its structure is: (1) Chloral (2) Gammaxene (3) Chloropicrin (4) Freon- 12

Q54.See the following chemical reaction: Cr2O72 - + XH+ + 6Fe2 + →YCr3 + + 6Fe3 + + ZH2O The sum of X, Y and Z is

Q55.The sum of oxidation state of the metals in Fe(CO)5 , VO2+ and WO3 is

Q55.When Fe0 . 93O is heated in presence of oxygen, it converts to Fe2O3. The number of correct statement/s from the following is ______ . A. The equivalent weight of Fe0 . 93O is Molecular0 . 79weight B. The number of moles of Fe2 + and Fe3 + in 1 mole of Fe0 . 93O is 0 . 79 and 0 . 14 respectively. C. Fe0 . 93O is metal deficient with lattice comprising of cubic closed packed arrangement of O2 - ions. D. The % composition of Fe2 + and Fe3 + in Fe0 . 93O is 85% and 15% respectively. Q56.5 g of NaOH was dissolved in deionized water to prepare a 450 mL stock solution. What volume (in mL) of this solution would be required to prepare 500 mL of 0 . 1 M solution ? Given : Molar Mass of Na, O and H is 23, 16 and 1 g mol – 1 respectively

Q56.In alkaline medium, the reduction of permanganate anion involves a gain of ____________ electrons.

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

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

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

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

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.

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