Practice Questions

Q33.The oxidation states of nitrogen in NO, NO2, N2O and NO−3 are in the order of : (1) NO−3 > NO2 > NO > N2O (2) NO2 > NO−3 > NO > N2O (3) N2O > NO2 > NO > NO−3 (4) NO > NO2 > N2O > NO−3

Q33.Monomer of Novolac is : (1) 3-Hydroxybutanoic acid. (2) 1, 3 -Butadiene and styrene. (3) phenol and melamine. (4) o-Hydroxymethylphenol.

Q34.The oxidation states of ′P′ in H4P2O7, H4P2O5 and H4P2O6, respectively, are : (1) 7, 5 and 6 (2) 5, 4 and 3 (3) 5, 3 and 4 (4) 6, 4 and 5

Q34.The number of water molecules in gypsum, dead burnt plaster and plaster of Paris, respectively are: (1) 2, 0 and 0. 5 (2) 0. 5, 0 and 2 (3) 2, 0 and 1 (4) 5, 0 and 0. 5

Q34.The set of elements that differ in mutual relationship from those of the other sets is: (1) Li −Mg (2) B −Si (3) Be −Al (4) Li −Na

Q34.The major component/ingredient of Portland Cement is : (1) dicalcium silicate (2) tricalcium aluminate (3) dicalcium aluminate (4) tricalcium silicate

Q34.Match List −I with List −II List −I List −II (a) Ca(OCl)2 (i) Antacid (b) CaSO4 ⋅12 H2O (ii) Cement (c) CaO (iii) Bleach (d) CaCO3 (iv) Plaster of paris Choose the most appropriate answer from the (1) a −i, b −iv, c −iii, d −ii (2) a −iii, b −ii, c −iv, d −i (3) a −iii, b −iv, c −ii, d −i (4) a −iii, b −ii, c −i, d −iv

Q34.What are the products formed in sequence when excess of CO2 is passed in slaked lime? (1) CaO, CaCO3 (2) Ca (HCO3)2′ CaCO3 (3) CaCO3, Ca (HCO3)2 (4) CaO, Ca (HCO3)2

Q34.The solubility of AgCN in a buffer solution of pH = 3 is x . The value of x is: [Assume : No cyano complex is formed ; Ksp(AgCN) = 2. 2 × 10−16 and Ka(HCN) = 6. 2 × 10−10 ] (1) 1. 9 × 10−5 (2) 2. 2 × 10−16 (3) 0. 625 × 10−6 (4) 1. 6 × 10−6

Q34.Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere. Reason R: Hydrogen is the lightest element. In the light of the above statements, choose the correct answer from the options given below: (1) Both A and R are true but R is NOT the correct (2) Both A and R are true and R is the correct explanation of A explanation of A (3) A is true but R is false (4) A is false but R true JEE Main 2021 (24 Feb Shift 2) JEE Main Previous Year Paper

Q35.Identify the process in which change in the oxidation state is five : (1) Cr2 O2−7 →2 Cr3+ (2) MnO−4 →Mn2+ (3) CrO2−4 →Cr3+ (4) C2O2−4 →2 CO2

Q35.Which purification technique is used for high boiling organic liquid compound (decomposes near its boiling point) ? (1) Simple distillation (2) Steam distillation (3) Fractional distillation (4) Reduced pressure distillation

Q35.One of the by-products formed during the recovery of NH3 from Solvay process is: (1) Ca(OH)2 (2) NaHCO3 (3) CaCl2 (4) NH4 Cl

Q36.Which one of the following metals forms interstitial hydride easily ? (1) Cr (2) Fe (3) Mn (4) Co JEE Main 2021 (25 Jul Shift 2) JEE Main Previous Year Paper

Q36.The single largest industrial application of dihydrogen is: (1) Manufacture of metal hydrides (2) Rocket fuel in space research (3) In the synthesis of ammonia (4) In the synthesis of nitric acid JEE Main 2021 (20 Jul Shift 2) JEE Main Previous Year Paper

Q36.In stratosphere most of the ozone formation is assisted by : (1) γ -rays (2) cosmic rays (3) visible radiations (4) ultraviolet radiation

Q36.Staggered and eclipsed conformers of ethane are: (1) Polymers (2) Rotamers (3) Enantiomers (4) Mirror images JEE Main 2021 (27 Jul Shift 1) JEE Main Previous Year Paper

Q37.Water sample is called cleanest on the basis of which one of the BOD values given below : (1) 11 ppm (2) 15 ppm (3) 3 ppm (4) 21 ppm

Q37.In chromatography technique, the purification of a compound is independent of: (1) Mobility or flow of solvent system (2) Solubility of the compound (3) Length of the column or TLC Plate (4) Physical state of the pure compound

Q37.Mesityl oxide is a common name of: (1) 2, 4 -Dimethylpentan- 3 -one (2) 3-Methylcyclohexanecarbaldehyde (3) 2-Methylcyclohexanone (4) 4-Methylpent- 3-en- 2-one

Q37.In the following molecules, Hybridisation of carbon a, b and c respectively are : JEE Main 2021 (18 Mar Shift 2) JEE Main Previous Year Paper (1) sp3, sp, sp (2) sp3, sp2, sp (3) sp3, sp2, sp2 (4) sp3, sp, sp2

Q37. BOD values (in ppm) for clean water (A) and polluted water (B) are expected respectively as: (1) A < 5, B > 17 (2) A > 50, B < 27 (3) A > 15, B > 47 (4) A > 25, B < 17

Q37.In CH21 = C2 = CH3 − CH34 molecule, the hybridization of carbon 1, 2, 3 and 4 respectively, are : (1) sp2, sp3, sp2, sp3 (2) sp2, sp, sp2, sp3 (3) sp2, sp2, sp2, sp3 (4) sp3, sp, sp3, sp3

Q37.Lyophilic sols are more stable than lyophobic sols because: (1) the colloidal particles have no charge. (2) the colloidal particles have positive charge. (3) the colloidal particles are solvated. (4) there is a strong electrostatic repulsion between the negatively charged colloidal particles.

Q37.Which one of the following chemical agent is not being used for dry-cleaning of clothes? (1) H2O2 (2) CCl4 (3) Liquid CO2 (4) Cl2C = CCl2