Practice Questions
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Q58.KClO3 + 6FeSO4 + 3H2SO4 โ KCl + 3Fe2 ( SO4 ) + 3H2O 3 The above reaction was studied at 300 K by monitoring the concentration of FeSO4 in which initial concentration was 10 M and after half an hour became 8 . 8 M. The rate of production of Fe2 ( SO4 ) is 3 _______ ร l0 โ 6 mol L โ 1 s โ 1 (Nearest integer)
Q58.Number of compounds from the following which will not produce orange red precipitate with Benedict solution is........ Glucose, maltose, sucrose, ribose, 2-deoxyribose, amylose, lactose JEE Main 2023 (11 Apr Shift 2) JEE Main Previous Year Paper
Q58.For the adsorption of hydrogen on platinum, the activation energy is 30 kJ mol โ 1 and for the adsorption of hydrogen on nickel, the activation energy is 41 . 4 kJ mol โ 1 . The logarithm of the ratio of the rates of chemisorption on equal areas of the metals at 300 K is _______ (Nearest integer) Given: In10 = 2 . 3 R = 8 . 3 J K-1 mol-1
Q58.A and B are two substances undergoing radioactive decay in a container. The half life of A is 15 min and that of B is 5 min. If the initial concentration of B is 4 times that of A and they both start decaying at the same time, how much time will it take for the concentration of both of them to be same? ________min.
Q58.A โB The rate constants of the above reaction at 200 K and 300 K are 0 . 03 min-1 and 0 . 05 min-1 respectively. The activation energy for the reaction is J (Nearest integer) (Given : In 10 = 2 . 3 R = 8 . 3 J K-1 mol-1 log 5 = 0 . 70 log 3 = 0 . 48 log2 = 0 . 30
Q58.Sea water contains 29 . 25 % NaCl and 19 % MgCl2 by weight of solution. The normal boiling point of the sea water is โC (Nearest integer) Assume 100% ionization for both NaCl and MgCl2 Given: KbH2O = 0 . 52 K kg mol-1 Molar mass of NaCl and MgCl2 is 58 . 5 and 95 g mol-1 respectively.
Q58.If compound A reacts with B following first order kinetics with rate constant 2 . 011 ร 10-3 s-1. The time taken by A (in seconds) to reduce from 7 g to 2 g will be _____ . (Nearest Integer) log5 = 0 . 698, log7 = 0 . 845, log2 = 0 . 301
Q58.The specific conductance of 0 . 0025M acetic acid is 5 ร 10-5 S cm-1 at a certain temperature. The dissociation constant of acetic acid is ___________ ร 10-7.(Nearest integer) Consider limiting molar conductivity of CH3COOH as 400 S cm2 mol-1
Q59.The oxidation sate of phosphorus in hypophosphoric acid is
Q59.Sum of oxidation states of bromine in bromic acid and perbromic acid is JEE Main 2023 (01 Feb Shift 1) JEE Main Previous Year Paper
Q59.In ammonium - phosphomolybdate, the oxidation state of Mo is +_______ JEE Main 2023 (06 Apr Shift 1) JEE Main Previous Year Paper
Q59.The number of incorrect statement/s from the following is ______________ A. The successive half lives of zero order reactions decreases with time. B. A substance appearing as reactant in the chemical equation may not affect the rate of reaction C. Order and molecularity of a chemical reaction can be a fractional number JEE Main 2023 (10 Apr Shift 2) JEE Main Previous Year Paper D. The rate constant units of zero and second order reaction are molL -1 s-1 and mol-1 L s-1 respectively
Q59.A molecule undergoes two independent first order reactions whose respective half lives are 12 min and 3 min. If both the reactions are occurring then the time taken for the 50% consumption of the reactant is ______ min. (Nearest integer)
Q59.The d-electronic configuration of CoCl4 2 - in tetrahedral crystal field is emt2n. The sum of m and number of unpaired electrons is
Q59.The volume (in mL) of 0. 1 M AgNO3 required for complete precipitation of chloride ions present in 20 mL of 0. 01 M solution of [Cr (H2O)5 Cl] Cl2 as silver chloride is_______
Q59.At 298 K, the standard reduction potential for Cu2 + / Cu electrode is 0 . 34 V. Given : = 0 . 059 V The reduction potential at pH = 14 for the above couple KspCu(OH ) 2 = 1 ร 10-20 Take 2 . 303RTF is ( - )๐ฅร 10-2 V. The value of x is
Q59.Given below are two statements: One is labelled as Assertion A and the other labelled as Reason R. Assertion A : Antihistamines do not affect the secretion of acid in stomach. Reason R : Antiallergic and antacid drugs work on different receptors. 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 true and R is the correct explanation of A (3) A is true but R is false (4) Both A and R are true but R is not the correct explanation of A .
Q59.The ratio of spin-only magnetic moment values 3 - + ฮผeffCr ( CN ) 6 / ฮผeffCrH2O63 is _______
Q59.The number of electrons involved in the reduction of permanganate to manganese dioxide in acidic medium is _____ .
Q60.A trisubstituted compound 'A', C10H12O2 gives neutral FeCl3 test positive. Treatment of compound 'A' with NaOH and CH3Br gives C11H14O2, with hydroiodic acid gives methyl iodide and with hot conc. NaOH gives a compound B, C10H12O2. Compound 'A' also decolorises alkaline KMnO4. The number of ๐ bond/s present in the compound 'A' is _____ .
Q60.Number of ambidentate ligands in a representative metal complex M ( en ) ( SCN ) is _________ . [en = 4 ethylenediamine]
Q60.In an oligopeptide named Alanylglycylphenyl alanyl isoleucine, the number of sp2 hybridised carbons is _____. is equal to
Q60.Number of isomeric compounds with molecular formula C9H10O which (i) do not dissolve in NaOH (ii) do not dissolve in HCl. (iii) do not give orange precipitate with 2, 4 - DNP (iv) on hydrogenation give identical compound with molecular formula C9H12O is
Q60.How many of the transformation given below would result in aromatic amines? JEE Main 2023 (31 Jan Shift 1) JEE Main Previous Year Paper
Q60. The ratio x/y on completion of the above reaction is ______ . JEE Main 2023 (11 Apr Shift 1) JEE Main Previous Year Paper ๐ฅ- 7 2