Practice Questions

Q37.In graphite and diamond, the percentage of p-characters of the hybrid orbitals in hybridization respectively, are (1) 33 and 25 (2) 67 and 75 (3) 50 and 75 (4) 33 and 75

Q37.In graphite and diamond, the percentage of p characters of the hybrid orbitals in hybridization are respectively: (1) 33 and 25 (2) 67 and 75 (3) 50 and 75 (4) 33 and 75

Q37.At 320 K, a gas A2 is 20 % dissociated to A(g) . The standard Gibbs free energy change at 320 K and 1 atm in J mol–1 is approximately: (R = 8 .314 JK–1 mol–1 ; ln 2 = 0 .693 ; ln 3 = 1 .098) (1) 1844 (2) 2068 (3) 4281 (4) 4763

Q37.At a certain temperature in a 5L vessel, 2 moles of carbon monoxide and 3 moles of chlorine were allowed to reach equilibrium according to the reaction, CO + Cl2 ⇌COCl2 . At equilibrium, if one mole of CO is present then equilibrium constant (Kc) for the reaction is: (1) 2.5 (2) 4 (3) 2 (4) 3

Q38.The decreasing order of bond angles in BF3, NH3, PF3 and I−3 is: (1) I−3 > BF3 > NH3 > PF3 (2) BF3 > I−3 > PF3 > NH3 (3) BF3 > NH3 > PF3 > I−3 (4) I−3 > NH3 > PF3 > BF3

Q38.The decreasing order of bond angles in BF3, NH3, PF3 and I−3 is : (1) I−3 > BF3 > NH3 > PF3 (2) BF3 > I−3 > PF3 > NH3 (3) BF3 > NH3 > PF3 > I−3 (4) I−3 > NH3 > PF3 > BF3

Q38.An aqueous solution contains an unknown concentration of Ba2+ . When 50 mL of a 1 M solution of Na2 SO4 is added, BaSO4 just begins to precipitate. The final volume is 500 mL. The solubility product of BaSO4 is 1 × 10−10 . What is the original concentration of Ba2+ ? (1) 1 .0 ×10−10M (2) 5 × 10−9M (3) 2 × 10−9M (4) 1 .1 ×10−9M

Q38.For which of the following processes, ΔS is negative? (1) C (diamond) →C (graphite) (2) N2(g, 1 atm) →N2(g, 5 atm) (3) N2(g, 273K) →N2(g, 300K) (4) H2(g) →2H(g)

Q38.Following four solutions are prepared by mixing different volumes of NaOH and HCl of different concentrations, pH of which one of them will be equal to 1 ? (1) 55 mL 10M HCl + 45 mL 10M NaOH (2) 75 mL M5 HCl + 25 mL M5 NaOH (3) 100 mL 10M HCl + 100 mL 10M NaOH (4) 60 mL 10M HCl + 40 mL 10M NaOH

Q39.For which of the following reactions, ΔH is equal to ΔU ? (1) N2 (g) + 3H2 (g) →2 NH3 (g) (2) 2 HI (g) →H2(g) + I2(g) (3) 2 SO2 (g) + O2 (g) →2 SO3 (g) (4) 2 NO2 (g) →N2O4 (g)

Q39.For standardizing NaOH solution, which of the following is used as a primary standard? (1) Sodium tetra borate (2) Ferrous Ammonium sulphate (3) Oxalic acid (4) Dil. HCl

Q39.For which of the following reactions, ΔH is equal to ΔU ? (1) N2(g) + 3H2(g) →2NH3(g) (2) 2HI(g) →H2(g) + I2(g) (3) 2SO2 (g) +O2(g) →2SO3(g) (4) 2NO2(g) →N2O4(g)

Q39.In KO2 , the nature of oxygen species and the oxidation state of oxygen atom are, respectively: (1) Superoxide and −1 (2) Superoxide and −1/2 (3) Peroxide and −1/2 (4) Oxide and −2

Q39.Which of the following are Lewis acids? (1) BCl3 and AlCl3 (2) PH3 and BCl3 (3) AlCl3 and CCl4 (4) PH3 and CCl4

Q40.Which of the following salts is the most basic in aqueous solution? JEE Main 2018 (08 Apr) JEE Main Previous Year Paper (1) Pb (CH3 COO)2 (2) Al (CN)3 (3) CH3 COOK (4) FeCl3

Q40.An ideal gas undergoes a cyclic process as shown in the figure ΔUBC = −5 KJmol−1, qAB = 2 KJmol−1 WAB = −5 KJmol−1, WCA = 3 KJmol−1 Heat absorbed by the system during process CA is (1) −5 KJmol−1 (2) +5 KJmol−1 (3) −18 KJmol−1 (4) 18 KJmol−1

Q40.The gas phase reaction 2 NO2(g) → N2O4 (g) is an exothermic reaction. The decomposition of N2O4 , in equilibrium mixture of NO2 (g) and N2O4 (g) can be increased by: (1) Addition of an inert gas at constant pressure (2) Lowering the temperature (3) Increasing the pressure (4) Addition of an inert gas at constant volume

Q40. An ideal gas undergoes a cyclic process as shown in Figure. ΔUBC = −5 kJ mol−1, qAB = 2 kJ mol−1 Heat absorbed by the system during process CA is: WAB = −5 kJ mol−1, WCA = 3 kJ mol−1 (1) −5 kJ mol−1 (2) +5 kJ mol−1 (3) 18 kJ mol−1 (4) −18 kJ mol−1

Q40.Lithium aluminium hydride reacts with silicon tetrachloride to form: (1) LiCl, AlH3 and SiH4 (2) LiCl, AlCl3 and SiH4 (3) LiH, AlCl3 and SiCl2 (4) LiH, AlH3 and SiH4 JEE Main 2018 (15 Apr Shift 2 Online) JEE Main Previous Year Paper

Q41.In which of the following reactions, an increase in the volume of the container will favour the formation of products? JEE Main 2018 (15 Apr) JEE Main Previous Year Paper (1) 4 NH3 (g) + 5O2 (g) ⇌ 4 NO(g) + 6H2O(l) (2) 2 NO2 (g) ⇌ 2 NO(g) + O2(g) (3) 3O2 (g) ⇌ 2O3(g) (4) H2 (g) + I2 (g) ⇌ 2HI(g)

Q41.An alkali is titrated against acid with methyl orange as an indicator, which of the following is a correct combination? (1) Base Acid End point (2) Base Acid End point Strong Strong Pink to colourless Weak Srtong Colourless to pink (3) Base Acid End point (4) Base Acid End point Strong strong Pinkish red to yellow Weak Strong Yellow to pinkish red

Q41.The total number of optically active compounds formed in the following reaction is: (1) Zero (2) Six (3) Four (4) Two

Q41.A group 13 element 'X' reacts with chlorine gas to produce a compound XCl3. XCl3 is electron deficient and easily reacts with NH3 to form Cl3 X ←NH3 adduct; however, XCl3 does not dimerize. X is: (1) B (2) Al (3) In (4) Ga JEE Main 2018 (16 Apr Online) JEE Main Previous Year Paper

Q41.In which of the following reactions, an increase in the volume of the container will favour the formation of products? (1) 4NH3(g) + 5O2(g) ⇌4NO (g) +6H2O(l) (2) 2NO2(g) ⇌2NO(g) + O2 (g) (3) 3O2 ⇌2O3(g) (4) H2(g) + I2(g) ⇌2HI(g)

Q42.On the treatment of the following compound with a strong acid, the most susceptible site for bond cleavage is: (1) O2 −C3 (2) O5-C6 (3) C4 −O5 (4) C1 −O2