Practice Questions

Q47.An organic compound 'A' on reaction with NH3 followed by heating gives compound B. Which on further strong heating gives compound C C8H5NO2. Compound C on sequential reaction with ethanolic KOH, alkyl chloride and hydrolysis with alkali gives a primary amine. The compound A is (1) (2) (3) (4)

Q47.An organic compound ' A ' contains nitrogen and chlorine. It dissolves readily in water to give a solution that turns litmus red. Titration of compound ' A ' with standard base indicates that the molecular weight of ' A ' is 131 ± 2 . When a sample of ' A ' is treated with aq. NaOH, a liquid separates which contains N but not Cl. Treatment of the obtained liquid with nitrous acid followed by phenol gives orange precipitate. The compound ' A ' is (1) (2) (3) (4)

Q50.When sugar ' X ' is boiled with dilute H2 SO4 in alcoholic solution, two isomers ' A' and ' B' are formed. ' A' on oxidation with HNO3 yields saccharic acid where as ' B' is laevorotatory. The compound ' X' is (1) Maltose (2) Sucrose (3) Lactose (4) Strach

Q52. PCl5 dissociates as PCl5(g) ⇌PCl3(g) + Cl2(g) 5 moles of PCl5 are placed in a 200 litre vessel which contains 2 moles of N2 and is maintained at 600 K. The equilibrium pressure is 2. 46 atm . The equilibrium constant Kp for the dissociation of PCl5 is___ ×10−3 . (nearest integer) (Given: R = 0. 082 L atm K−1 mol−1 ; Assume ideal gas behaviour)

Q53.for a real gas at 25 °C temperature and high pressure ( 99 bar) the value of compressibility factor is 2 , so the value of Van 1der Waal's constant ' b' should be_____ ×10−2 L mol−1 (Given R = 0. 083 L bar K−1 mol−1 )

Q54.Compound ' P' on nitration with dil. HNO3 yields two isomers (A) and (B). These isomers can be separated by steam distillations. Isomers (A) and (B) show the intramolecular and intermolecular hydrogen bonding respectively. Compound (P) on reaction with conc. HNO3 yields a yellow compound ' C', a strong acid. The number of oxygen atoms is present in compound ' C'

Q54.The major product ' A' of the following given reaction has sp2 hybridized carbon atoms. JEE Main 2022 (24 Jun Shift 1) JEE Main Previous Year Paper H+ 2, 7 -Dimethyl- 2, 6 -octadiene → A Major Product

Q55.In the estimation of bromine, 0. 5 g of an organic compound gave 0. 40 g of silver bromide. The percentage of bromine in the given compound is % (nearest integer) (Relative atomic masses of Ag and Br are 108u and 80u , respectively).

Q56.The standard free energy change ΔG° for 50% dissociation of N2O4 into NO2 at 27 °C and 1 atm pressure is -x J mol-1. The value of x is - . . . . . J. (Nearest Integer) [Given : R = 8 . 31 J K-1 mol-1, log1 . 33 = 0 . 1239 ln10 = 2 . 3]

Q56.The cell potential for the given cell at 298 K Pt|H2(g, 1 bar)| H+(aq) Cu2+(aq) Cu(s) is 0. 31 V . The pH of the acidic solution is found to be 3, whereas the concentration of Cu2+ is 10x M. The value of x is _________. (Given: EΘ = 0. 34 V and 2.303F RT = 0. 06 V ) Cu2+ / Cu JEE Main 2022 (29 Jun Shift 2) JEE Main Previous Year Paper

Q57.The distance between Na+ and Cl- ions in solid NaCl of density 43 . 1 gcm-3 is . . . . . × 10-10 m. (Nearest Integer) (Given : NA = 6 . 02 × 1023 mol-1)

Q57.Resistance of a conductivity cell (cell constant 129 m−1 ) filled with 74. 5 ppm solution of KCl is 100 Ω (labelled as solution 1). When the same cell is filled with KCl solution of 149 ppm, the resistance is 50 Ω (labelled as solution 2). The ratio of molar conductivity of solution 1 and solution 2 is i.e. ∧1 = x × 10−3 . The ∧2 value of x is____Given, molar mass of KCl is 74. 5 g mol−1 )

Q58.Amongst FeCl3 . 3H2O, K3FeCN6 and CoNH36Cl3, the spin-only magnetic moment value of the inner-orbital complex that absorbs light at shortest wavelength is B.M. [nearest integer]

Q58.The number of terminal oxygen atoms present in the product B obtained from the following reaction is FeCr2 O4 + Na2 CO3 + O2 →A + Fe2 O3 + CO2 A + H+ →B + H2O + Na+

Q58.Total number of isomers (including stereoisomers) obtain on monochlorination of methylcyclohexane is

Q58.The quantity of electricity in Faraday needed to reduce 1 mol of Cr2 O2−7 to Cr3+ is

Q59.Consider the following metal complexes : CoNH3 3 + CoClNH35 2 + 3 - Co ( CN ) 6 CoNH35H2O3 + The spin-only magnetic moment value of the complex that absorbs light with shortest wavelength is B.M. (Nearest integer)

Q60.A sample of 4. 5 mg of an unknown monohydric alcohol, R −OH was added to methylmagnesium iodide. A gas is evolved and is collected and its volume measured to be 3. 1 mL. The molecular weight of the unknown alcohol is g/ mol. p is _______.

Q60.Reaction of [Co (H2O)6]2+ with excess ammonia and in the presence of oxygen results into a diamagnetic product. Number of electrons present in t2g -orbitals of the product is 1 (−1)n A

Q61.For z ∈C if the minimum value of ( z −3√2 + z −p√2i ) is 5√2 , then a value of (1) 3 (2) 72 (3) 4 (4) 92

Q35.Which of the following equation depicts the oxidizing nature of H2O2 ? (1) 2I−+ H2O2 + 2H+ →I2 + 2H2O (2) I2 + H2O2 + 2 OH−→2I−+ 2H2O + O2 (3) Cl2 + H2O2 →2HCl + O2 (4) KIO4 + H2O2 →KIO3 + H2O + O2

Q36. Correct statement about the given chemical reaction is (1) Reaction is possible and compound (A) will be (2) −¨NH2 group is ortho and para directive, so major product. product (B) is not possible. (3) Reaction is possible and compound (B) will be (4) The reaction will form sulphonated product the major product. instead of nitration.

Q37.What is the correct sequence of reagents used for converting nitrobenzene into m -dibromobenzene? (1) Sn / HCl KBr Br2 H+ (2) Br2 / Fe Sn / HCl NaNO2 / HCl CuBr / HBr−−−−−−→ / → / →/ → → / → / → / → (3) NaNO2 HCl KBr H+ (4) Sn / HCl Br2 NaNO2 NaBr−−−−−−→ / → / → / → → / →/ → / →

Q38.The correct sequence of correct reagents for the following transformation is :- (1) (i) Fe, HCl (2) (i) Fe, HCl (ii) Cl2, HCl, (ii) NaNO2, HCl, 0°C (iii) NaNO2, HCl, 0°C (iii) H2O/H+ (iv) H2O/H+ (iv) Cl2, FeCl3 (3) (i) Cl2, FeCl3 (4) (i) Cl2, FeCl3 (ii) Fe, HCl (ii) NaNO2, HCl, 0°C (iii) NaNO2, HCl, 0°C (iii) Fe, HCl (iv) H2O/H+ (iv) H2O/H+

Q38.The correct sequence of reagents used in the preparation of 4 -bromo- 2-nitroethylbenzene from benzene is : JEE Main 2021 (25 Feb Shift 2) JEE Main Previous Year Paper (1) CH3 COCl / AlCl3, Br2 / AlBr3, HNO3 /H2 SO4, Zn / HCl (2) CH3 COCl / AlCl3, Zn −Hg / HCl, Br2 / AlBr3, HNO3 /H2 SO4 (3) HNO3 /H2 SO4, Br2 / AlCl3, CH3 COCl / AlCl3, Zn −Hg / HCl (4) Br2 / AlBr3, CH3 COCl / AlCl3, HNO3 /H2 SO4, Zn / HCl