Practice Questions
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Q31.Hydrogen peroxide, in the pure state, is : (1) non–planar and almost colorless (2) Linear and blue in color (3) Linear and almost colorless (4) planar and blue in color
Q31.An open beaker of water in equilibrium with water vapour is in a sealed container. When a few grams of glucose are added to the beaker of water, the rate at which water molecules : (1) leaves the vapour increases (2) leaves the solution increases (3) leaves the solution decreases (4) leaves the vapour decreases
Q31.The Ksp for the following dissociation is 1.6 × 10−5 PbCl2(s) ⇌Pb2+(aq) + 2Cl−(aq) Which of the following choices is correct for a mixture of 300 mL 0.134 M Pb(NO3)2 and 100 mL 0.4 M NaCl? (1) Not enough data provided (2) Q < Ksp (3) Q > Ksp (4) Q = Ksp JEE Main 2020 (09 Jan Shift 1) JEE Main Previous Year Paper
Q31.Among statements (a) −(d), the correct ones are: (a) Decomposition of hydrogen peroxide gives di-oxygen. (b) Like hydrogen peroxide, compounds, such as KClO3, Pb(NO3) and NaNO3 When heated liberate di- oxygen. (c) 2 -Ethylanthraquinone is useful for the industrial preparation of hydrogen peroxide. (d) Hydrogen peroxide is used for the manufacture of sodium perborate. (1) (a), (b), (c) and (d) (2) (a), (b), and (c) only (3) (a), (c), and (d) only (4) (a) and (c) only
Q31.Oxidation number of potassium in K2O, K2O2 and KO2, respectively, is: (1) +2, + 1 and + 21 (2) +1, + 1 and +1 (3) +1, + 4 and +2 (4) +1, + 2 and +4
Q31.Glycerol is separated in soap industries by : (1) Fractional distillation (2) Differential distillation (3) Steam distillation (4) Distillation under reduced pressure
Q31.The increasing order of the acidity of the α-hydrogen of the following compounds is: (A) (B) (C) (D) (1) (D) < (C) < (A) < (B) (2) (B) < (C) < (A) < (D) (3) (A) < (C) < (D) < (B) (4) (C) < (A) < (B) < (D)
Q31.The strength of an aqueous NaOH solution is most accurately determined by titrating: (Note: consider that an appropriate indicator is used) (1) Aq. NaOH in a pipette and aqueous oxalic acid (2) Aq. NaOH in a burette and aqueous oxalic acid in a burette in a conical flask (3) Aq. NaOH in a burette and concentrate H2SO4 (4) Aq. NaOH in a volumetric flask and in a conical flask concentrated H2SO4 in a conical flask
Q31.Which of the following compounds shows geometrical isomerism? (1) 2-methylpent-2-ene (2) 4-methylpent-2-ene (3) 4-methylpent-1-ene (4) 2-methylpent-1-ene
Q31.Among the reactions (a) −(d), the reaction(s) that does/do not occur in the blast furnace during the extraction of iron is/are: (a) CaO + SiO2 →CaSiO3 (b) 3Fe2O3 + CO →2Fe3O4 + CO2 (c) FeO + SiO2 →FeSiO3 (d) FeO →Fe + 21 O2 (1) a (2) a and d (3) c and d (4) d
Q31.Match the following : Test/Method Reagent (i) Lucas Test (a) C6H5 SO2 Cl / aq. KOH (ii) Dumas method (b) HNO3 / AgNO3 (iii) Kjeldahl's method (c) CuO / CO3 (iv) Hinsberg Test (d) Conc. HCl and ZnCl2 (e) H2 SO4 (1) (i)-(d), (ii)-(c), (iii)-(b), (iv)-(e) (2) (i)-(b), (ii)-(d), (iii)-(e), (iv)-(a) (3) (i)-(d), (ii)-(c), (iii)-(e), (iv)-(a) (4) (i)-(b), (ii)-(a), (iii)-(c), (iv)-(d)
Q31.If the equilibrium constant for A ⇌B + C is K(1)eq and that of B + C ⇌P is K(2)eq , the equilibrium constant for A ⇌P is : (1) K(1)eq /K(2)eq (2) K(2)eq −K(1)eq (3) K(1)eq + K(2)eq (4) K(1)eq K(2)eq
Q32.On heating, lead (ll) nitrate gives a brown gas (A). The gas (A) on cooling changes to a colourless solid/liquid (B). (B) on heating with NO changes to ablue solid (C). The oxidation number of nitrogen in solid (C) is: (1) +5 (2) +2 (3) +3 (4) +4
Q32. Arrange the following labelled hydrogens in decreasing order of acidity: (1) b > a > c > d (2) c > b > a > d (3) b > c > d > a (4) c > b > d > a
Q32.The compound that cannot act both as oxidizing and reducing agent is (1) H3PO4 (2) H NO2 (3) H2SO3 (4) H2O2 Q33.‘ X ’ melts at low temperature and is a bad conductor of electricity in both liquid and solid state. X is: (1) zinc sulphide (2) Mercury (3) Silicon carbide (4) Carbon tetrachloride
Q32.The correct order of stability for the following alkoxides is: (1) (B) > (A) > (C) (2) (C) > (B) > (A) (3) (C) > (A) > (B) (4) (B) > (C) > (A)
Q32.The one that is NOT suitable for the removal of permanent hardness of water is : (1) Clark's method (2) Ion–exchange method (3) Calgon's method (4) Treatment with sodium carbonate
Q32.While titration dilute HCI solution with aqueous NaOH, which of the following will not be required ? (1) Burette and porcelain tile (2) Pipette and distilled water (3) Clamp and phenolphthalein (4) Bunsen burner and measuring cyclinder
Q32.Among the statements (a) −(d), the correct ones are: (a) Lithium has the highest hydration enthalpy among the alkali metals. (b) Lithium chloride is insoluble in pyridine. (c) Lithium cannot form ethynide upon its reaction with ethyne. (d) Both lithium and magnesium react slowly with H2O . (1) (a), (b) and (d) only (2) (a), (c) and (d) only (3) (b) and (c) only (4) (a) and (d) only
Q32.An alkaline earth metal ' M' readily forms water soluble sulphate and water insoluble hydroxide. Its oxide MO is very stable to heat and does not have rock-salt structure. M is (1) Sr (2) Ca (3) Mg (4) Be
Q32.In comparison to the zeolite process for the removal of permanent hardness, the synthetic resin method is (1) less efficient as it exchanges only anions. (2) more efficient as it can exchange both cations as well as anions. (3) less efficient as the resins cannot be regenerated. (4) more efficient as it can exchange only cations.
Q32.When gypsum is heated to 393K, it forms: (1) Anhydrous CaSO4 (2) CaSO4 ⋅5H2O (3) CaSO4 ⋅0.5H2O (4) Dead burnt plaster
Q32.Among the statement (I – IV), the correct ones are: (I) Be has smaller atomic radius compared to Mg. (II) Be has higher ionization enthalpy than AI. (III) Charge/radius ratio of Be is greater than that of Al. (IV) Both Be and Al form mainly covalent compounds (1) (I), (II) and (IV) (2) (I), (III) and (IV) (3) (II), (III) and (IV) (4) (I), (II) and (III) JEE Main 2020 (03 Sep Shift 2) JEE Main Previous Year Paper
Q32.The IUPAC name of following compound is : (1) 2-nitro- 4-hydroxymethyl- 5-amino benzaldehyde (2) 3-amino- 4-hydroxymethyl- 5-nitrogenzaldehyde (3) 5-amino- 4-hydroxymethyl- 2-nitrobenzaldehyde (4) 4-amino- 2-formyl- 5-hydroxymethyl nitrogenzene
Q32.In the following reaction sequence the major products A and B are : JEE Main 2020 (05 Sep Shift 1) JEE Main Previous Year Paper (1) (2) (3) (4)