Practice Questions
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Q38. Identify (B) and (C) and how are (A) and (C) related ? (1) (2) (3) (4)
Q38.Functional group present in sulphonic acids is : (1) −SO4H (2) −SO3H (3) (4) −SO2 JEE Main 2024 (06 Apr Shift 1) JEE Main Previous Year Paper
Q38.The correct stability order of the following resonance structures of CH3 −CH = CH −CHO is (1) I > II > III (2) II > III > I (3) II > I > III (4) III > II > I
Q38.Chromatographic technique/s based on the principle of differential adsorption is/are A. Column chromatography B. Thin layer chromatography C. Paper chromatography Choose the most appropriate answer from the options given below: (1) B only (2) A only (3) A & B only (4) C only
Q38.Common name of Benzene - 1, 2 - diol is - (1) catechol (2) o-cresol (3) quinol (4) resorcinol
Q38.Relative stability of the contributing structures is : (1) (I) > (II) > (III) (2) (I) > (III) > (II) (3) (II) > (I) > (III) (4) (III) > (II) > (I)
Q39.Which of the following has highly acidic hydrogen? (1) (2) (3) (4)
Q39.Arrange the following elements in the increasing order of number of unpaired electrons in it. (A) Sc (B) Cr (C) V (D) Ti (E) Mn Choose the correct answer from the options given below : (1) (A) < (D) < (C) < (B) < (E) (2) (C) < (E) < (B) < (A) < (D) (3) (A) < (D) < (C) < (E) < (B) (4) (B) < (C) < (D) < (E) < (A)
Q39.Which of the following statements is not correct about rusting of iron? JEE Main 2024 (27 Jan Shift 2) JEE Main Previous Year Paper (1) Coating of iron surface by tin prevents rusting, (2) When pH lies above 9 or 10 , rusting of iron does even if the tin coating is peeling off. not take place. (3) Dissolved acidic oxides SO2, NO2 in water act as (4) Rusting of iron is envisaged as setting up of catalyst in the process of rusting. electrochemical cell on the surface of iron object.
Q39.The solution from the following with highest depression in freezing point/lowest freezing point is (1) 180 g of acetic acid dissolved in 1 L of (2) 180 g of acetic acid dissolved in benzene aqueous solution. (3) 180 g of benzoic acid dissolved in benzene (4) 180 g of glucose dissolved in water
Q39.In qualitative test for identification of presence of phosphorous, the compound is heated with an oxidising agent. Which is further treated with nitric acid and ammonium molybdate respectively. The yellow coloured precipitate obtained is : (1) Na3PO4 ⋅12MoO3 (2) (NH4)3PO4 ⋅12MoO3 (3) MoPO4.21NH4NO3 (4) (NH4)3PO4 ⋅12(NH4)2MoO4
Q39.Anomalous behaviour of oxygen is due to its (1) Large size and high electronegativity (2) Small size and low electronegativity (3) Small size and high electronegativity (4) Large size and low electronegativity
Q39.The product (C) in the below mentioned reaction is: KOHalc HBr ∆ CH3 - CH2 - CH2 - Br →∆ A → B →KOHaq C (1) Propan-1-ol (2) Propene (3) Propyne (4) Propan-2-ol
Q39.Appearance of blood red colour, on treatment of the sodium fusion extract of an organic compound with FeSO4 in presence of concentrated H2 SO4 indicates the presence of element/s (1) Br (2) N (3) N and S (4) S
Q39.In the given reactions identify the reagent A and reagent B (1) A −CrO3 B −CrO3 (2) A − CrO3 B −CrO2 Cl2 (3) A −CrO2 Cl2 B −CrO2 Cl2 (4) A −CrO2 Cl2 B −CrO3
Q39.The set of meta directing functional groups from the following sets is: (1) -CN, - NH2, - NHR, - OCH3 (2) -NO2, - NH2, - COOH, - COOR (3) -NO2, - CHO, - SO3H, - COR (4) -CN, - CHO, - NHCOCH3, - COOR
Q39.The adsorbent used in adsorption chromatography is/are - A. silica gel B. alumina C. quick lime D. magnesia Choose the most appropriate answer from the options given below : (1) A only (2) B only (3) C and D only (4) A and B only
Q39.Identify A and B in the given chemical reaction sequence : JEE Main 2024 (05 Apr Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)
Q39. Total number of stereo isomers possible for the given structure : (1) 2 (2) 4 (3) 3 (4) 8
Q39.The fragrance of flowers is due to the presence of some steam volatile organic compounds called essential oils. These are generally insoluble in water at room temperature but are miscible with water vapour in the vapour phase. A suitable method for the extraction of these oils from the flowers is: (1) crystallisation (2) distillation under reduced pressure (3) distillation (4) steam distillation
Q39.Identify the product A and product B in the following set of reactions. (1) (2) A - CH3CH2CH3 B −CH3CH2CH3 (3) A −CH3CH2CH2 −OH B −CH3CH2CH2 −OH (4)
Q39.The Molarity (M) of an aqueous solution containing 5.85 g of NaCl in 500 mL water is : (Given : Molar Mass Na : 23 and Cl : 35.5gmol−1 ) (1) 2 (2) 20 (3) 4 (4) 0.2
Q39.Which of the following statements are correct? A. Glycerol is purified by vacuum distillation because it decomposes at its normal boiling point. B. Aniline can be purified by steam distillation as aniline is miscible in water. C. Ethanol can be separated from ethanol water mixture by azeotropic distillation because it forms azeotrope. D. An organic compound is pure, if mixed M.P. is remained same. Choose the most appropriate answer from the options given below : (1) A, B, C only (2) A, C, D only (3) A, B, D only (4) B, C, D only
Q40.Identify the mixture that shows positive deviations from Raoult's Law (1) ( CH3 ) 2CO + C6H5NH2 (2) CHCl3 + C6H6 ) (3) CHCl3 + ( CH3 ) 2CO (4) ( CH3 2CO + CS2
Q40.Reduction potential of ions are given below: ClO4- IO4- BrO4- E° = 1 . 19 V ; E° = 1 . 65 V; E° = 1 . 74 V The correct order of their oxidising power is: (1) ClO4- > IO4- > BrO4- (2) BrO4- > IO4- > ClO4- (3) BrO4- > ClO4- > IO4- (4) IO4- > BrO4- > ClO4-