Practice Questions
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Q47.Which one the following compounds will readily react with dilute NaOH ? (1) C2H5OH (2) C6H5OH (3) C6H5CH2OH (4) (CH3)3COH
Q47.Identify the name reaction. (1) Stephen reaction (2) Etard reaction (3) Gatterman-koch reaction (4) Rosenmund reduction
Q47.Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R: Assertion A: 𝑝𝐾𝑎 value of phenol is 10 . 0 while that of ethanol is 15 . 9. Reason R: Ethanol is stronger acid than phenol. In the light of the above statements, choose the correct answer from the options given below: (1) A is true but R is false (2) A is false but R is true (3) Both A and R are true and R is the correct (4) Both A and R are true but R is NOT the correct explanation of A explanation of A.
Q47.Phenolic group can be identified by a positive: (1) Phthalein dye test (2) Lucas test (3) Tollen’s test (4) Carbylamine test
Q48.The correct statement regarding nucleophilic substitution reaction in a chiral alkyl halide is ; (1) Retention occurs in SNl reaction and inversion (2) Racemisation occurs in SNl reaction and occurs in SN2 reaction. retention occurs in SN2 reaction. (3) Racemisation occurs in both SN1 and SN2 (4) Racemisation occurs in SN1 reaction and reactions. inversion occurs in SN2 reaction.
Q48.Match List – I with List –II. JEE Main 2024 (01 Feb Shift 1) JEE Main Previous Year Paper Choose the correct answer from options given below: (1) A - III, B - IV, C - I, D - II (2) A - IV, B - II, C - I, D - III (3) A - IV, B - II, C - III, D - I (4) A - III, B - IV, C - II, D - I
Q48. Identify the product in the following reaction : (1) (2) (3) (4)
Q48.On passing a gas, ' X ', through Nessler's reagent, a brown precipitate is obtained. The gas ' X ' is (1) H2S (2) CO2 (3) NH3 (4) Cl2
Q49. Acid D formed in above reaction is: (1) Gluconic acid (2) Succinic acid (3) Oxalic acid (4) Malonic acid
Q49.Type of amino acids obtained by hydrolysis of proteins is : (1) β (2) α (3) δ (4) γ
Q49. Match List - I with List - II. Choose the correct answer from the options given below : (1) (A)-(IV), (B)-(II), (C)-(III), (D)-(I) (2) (A)-(I), (B)-(IV), (C)-(II), (D)-(III) (3) (A)-(III), (B)-(II), (C)-(I), (D)-(IV) (4) (A)-(II), (B)-(IV), (C)-(I), (D)-(III)
Q49.A reagent which gives brilliant red precipitate with Nickel ions in basic medium is (1) sodium nitroprusside (2) neutral FeCl3 (3) meta-dinitrobenzene (4) dimethyl glyoxime
Q50.Which of the following gives a positive test with ninhydrin? (1) Starch (2) Egg albumin (3) Polyvinyl chloride (4) Cellulose Q51. 9.3 g of pure aniline is treated with bromine water at room temperature to give a white precipitate of the product ' P '. The mass of product ' P ' obtaind is 26.4 g. The percentage yield is _______ % .
Q50. The incorrect statements regarding enzymes are : (A) Enzymes are biocatalysts. (B) Enzymes are non-specific and can catalyse different kinds of reactions. (C) Most Enzymes are globular proteins. (D) Enzyme - oxidase catalyses the hydrolysis of maltose into glucose. Choose the correct answer from the option given below : (1) (B), (C) and (D) (2) (B) and (D) (3) (A), (B) and (C) (4) (B) and (C)
Q50.Sugar which does not give reddish brown precipitate with Fehling's reagent is: JEE Main 2024 (30 Jan Shift 1) JEE Main Previous Year Paper (1) Sucrose (2) Lactose (3) Glucose (4) Maltose Q51. 0. 05 cm thick coating of silver is deposited on a plate of 0. 05 m2 area. The number of silver atoms deposited on plate are _______ ×1023 . (At mass Ag = 108, d = 7. 9 g cm−3) Round off to the nearest integer.
Q50.Which structure of protein remains intact after coagulation of egg white on boiling? (1) Primary (2) Tertiary (3) Secondary (4) Quaternary
Q50.Coagulation of egg, on heating is because of : JEE Main 2024 (05 Apr Shift 2) JEE Main Previous Year Paper (1) The secondary structure of protein remains (2) Denaturation of protein occurs unchanged (3) Biological property of protein remains unchanged(4) Breaking of the peptide linkage in the primary structure of protein occurs
Q50.If one strand of a DNA has the sequence ATGCTTCA, sequence of the bases in complementary strand is: (1) CATTAGCT (2) TACGAAGT (3) GTACTTAC (4) ATGCGACT
Q50.Two nucleotides are joined together by a linkage known as : (1) Phosphodiester linkage (2) Glycosidic linkage (3) Disulphide linkage (4) Peptide linkage
Q51.Wavenumber for a radiation having 5800Ã … wavelength is x × 10 cm−1 . The value of x is ________ (Integer answer)
Q51.Volume of 3M NaOH (formula weight 40 g mol-1 ) which can be prepared from 84 g of NaOH is ____ × 10-1dm3. Q52.9 . 3 g of aniline is subjected to reaction with excess of acetic anhydride to prepare acetanilide. The mass of acetanilide produced if the reaction is 100% completed is _____ × 10-1 g. (Given molar mass in g mol-1 N = 14, O = 16, C = 12, H = 1 ) Q53.1 mole of PbS is oxidised by X moles of O3 to get Y moles of O2 . X + Y =
Q51.Mass of methane required to produce 22 g of CO after complete combustion is g. (Given Molar mass in g mol- 1, C = 12. 0, H = 1. 0, O = 16. 0)
Q51.The maximum number of orbitals which can be identified with n = 4 and ml = 0 is ______ JEE Main 2024 (04 Apr Shift 2) JEE Main Previous Year Paper
Q51. A hypothetical electromagnetic wave is show below. The frequency of the wave is x × 1019 Hz . x = ______ (nearest integer)
Q51.Number of moles of methane required to produce 22g CO2 ( g ) after combustion is x × 10 – 2 moles. The value of x is