Practice Questions

Q53.An amine (X) is prepared by ammonolysis of benzyl chloride. On adding p-toluenesulphonyl chloride to it the solution remains clear. Molar mass of the amine (X) formed is ______ gmol−1 . (Given molar mass in gmol−1C : 12, H : 1, O : 16, N : 14)

Q53.The enthalpy of formation of ethane (C2H6) from ethylene by addition of hydrogen where the bond-energies of C −H, C −C, C = C, H −H are 414 kJ, 347 kJ, 615 kJ and 435 kJ respectively is kJ

Q53. Consider the figure provided. 1 mol of an ideal gas is kept in a cylinder, fitted with a piston, at the position A, at 18∘C . If the piston is moved to position B , keeping the temperature unchanged, then ' x ' L atm work is done in this reversible process. x = ______ L atm. (nearest integer) [Given : Absolute temperature = ∘C + 273.15, R = 0.08206 L atm mol−1 K−1 ]

Q53.In the lewis dot structure for NO−2 , total number of valence electrons around nitrogen is _______ JEE Main 2024 (05 Apr Shift 1) JEE Main Previous Year Paper

Q54.Total number of ions from the following with noble gas configuration is Sr2 + (Z = 38), Cs+ (Z = 55), La2 + (Z = 57)Pb2 + (Z = 82), Yb2 + (Z = 70) and Fe2 + (Z = 26)

Q54. The number of optical isomers in following compound is: ________

Q54.The major product of the following reaction is P . CH3C = C −CH3 (i) Na/ ing NH3→ Number of oxygen (ii) dil. KMnO4 273 K atoms present in product ' P ' is _______ (nearest integer)

Q54.Ka for CH3COOH is 1 . 8 × 10-5 and Kb for NH4OH is 1 . 8 × 10-5 . The pH of ammonium acetate solution will be

Q54.Consider the following reaction at 298 K. 3 2O2g ⇌O3g . Kp = 2 . 47 × 10-29 ∆rG0 for the reaction is _________ kJ. (Given R = 8 . 314 JK – 1 mol – 1) Round off your answer to the nearest integer.

Q54.If three moles of an ideal gas at 300 K expand isothermally from 30 dm3 to 45 dm3 against a constant opposing pressure of 80 kPa, then the amount of heat transferred is __________J.

Q54.Only 2 mL of KMnO4 solution of unknown molarity is required to reach the end point of a titration of 20 mL of oxalic acid (2M) in acidic medium. The molarity of KMnO4 solution should be M.

Q54.Number of compounds among the following which contain sulphur as heteroatom is____. Furan,Thiophene, Pyridine, Pyrrole, Cysteine, Tyrosine JEE Main 2024 (29 Jan Shift 1) JEE Main Previous Year Paper

Q54.Total number of species from the following which can undergo disproportionation reaction ___________. H2O2, ClO3- , P4, Cl2, Ag, Cu+1, F2, NO2, K+

Q54.The heat of solution of anhydrous CuSO4 and CuSO4 ⋅5H2O are −70 kJ mol−1 and +12 kJ mol−1 respectively. The heat of hydration of CuSO4 to CuSO4 ⋅5H2O is −x kJ . The value of x is ______ (nearest integer).

Q54.Total number of optically active compounds from the following is ______

Q54.Number of isomeric products formed by monochlorination of 2-methylbutane in presence of sunlight is _______.

Q54.Total number of isomeric compounds (including stereoisomers) formed by monochlorination of 2- methylbutane is ______.

Q55.Number of compounds from the following which cannot undergo Friedel-Crafts reactions is: ________. toluene, nitrobenzene, xylene, cumene, aniline, chlorobenzene, m-nitroaniline, m-dinitrobenzene JEE Main 2024 (09 Apr Shift 2) JEE Main Previous Year Paper

Q55.Mass of ethylene glycol (antifreeze) to be added to 18 . 6 kg of water to protect the freezing point at -24°C is kg (Molar mass in gmol-1 for ethylene glycol 62, Kf of water = 1 . 86 K kg mol-1)

Q55.The following concentrations were observed at 500 K for the formation of NH3 from N2 and H2 . At equilibrium : [N2] = 2 × 10−2M, [H2] = 3 × 10−2M and [NH3] = 1. 5 × 10−2M. Equilibrium constant for the reaction is ______.

Q55.The number of non-polar molecules from the following is HF, H2O, SO2, H2, CO2, CH4, NH3, HCl, CHCl3, BF3

Q55. Consider the given reaction. The total number of oxygen atoms present per molecule of the product (P) is _________.

Q55.Number of alkanes obtained on electrolysis of a mixture of CH3COONa and C2H5COONa is_____.

Q55.A solution containing 10 g of an electrolyte AB2 in 100 g of water boils at 100.52∘C . The degree of ionization of the electrolyte (α) is _______ ×10−1 . (nearest integer) [Given : Molar mass of AB2 = 200 g mol−1, Kb (molal boiling point elevation const. of water) = 0.52 K kg mol−1 , boiling point of water = 100∘C; AB2 ionises as AB2 →A2+ + 2 B−]

Q55.An artificial cell is made by encapsulating 0.2M glucose solution within a semipermeable membrane. The osmotic pressure developed when the artificial cell is placed within a 0.05M solution of NaCl at 300 K is _______ ×10−1 bar. (nearest integer). [Given : R = 0.083 Lbarmol−1 K−1 ] Assume complete dissociation of NaCl