Practice Questions

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.Using the given figure, the ratio of Rf values of sample A and sample C is x × 10−2 . Value of x is ______

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

Q54.An ideal gas undergoes a cyclic transformation starting from the point A and coming back to the same point by tracing the path A →B →C →A as shown in the diagram. The total work done in the process is _____ J.

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.For the reaction at 298 K, 2 A + B →C. ΔH = 400 kJ mol−1 and ΔS = 0.2 kJ mol−1 K−1 . The reaction will become spontaneous above K.

Q54. In the given TLC, the distance of spot A & B are 5 cm & 7 cm, from the bottom of TLC plate, respectively. Rf value of B is x × 10−1 times more than A . The value of x is ______.

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

Q54.The heat of combustion of solid benzoic acid at constant volume is −321.30 kJ at 27∘C . The heat of combustion at constant pressure is (−321.30 −xR)kJ , the value of x is _______.

Q54.The total number of 'sigma' and 'Pi' bonds in 2-oxohex-4-ynoic acid is ______ Q55. 2.7 kg of each of water and acetic acid are mixed. The freezing point of the solution will be −x∘C . Consider the acetic acid does not dimerise in water, nor dissociates in water. x = ______ (nearest integer) [Given: Molar mass of water = 18 g mol−1 , acetic acid = 60 g mol−1 KfH2O : 1.86 K kg mol−1 Kf acetic acid: 3.90 K kg mol−1 freezing point: H2O = 273 K, acetic acid = 290 K]

Q55.Number of optical isomers possible for 2 – chlorobutane ........

Q55.Among the following, total number of meta directing functional groups is (Integer based) −OCH3, −NO2, −CN, −CH3 −NHCOCH3 , −COR, −OH, −COOH, −Cl

Q55.The pH at which Mg(OH)2[ Ksp = 1 × 10−11] begins to precipitate from a solution containing 0. 10M Mg2+ ions is ______. Q56. 2 MnO−4 + bI−+ cH2 O →xI2 + yMnO2 + zOH− If the above equation is balanced with integer coefficients, the value of z is ________.

Q55.How many compounds among the following compounds show inductive, mesomeric as well as hyperconjugation effects?

Q55.Consider the two different first order reactions given below A + B →C (Reaction 1 ) P →Q (Reaction 2) The ratio of the half life of Reaction 1 : Reaction 2 is 5 : 2. If t1 and t2 represent the time taken to complete 2/3rd and 45th of Reaction 1 and Reaction 2, respectively, then the value of the ratio t1 : t2 is ______ ×10−1 (nearest integer). [Given : log10(3) = 0.477 and log10(5) = 0.699]

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

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

Q55.Considering acetic acid dissociates in water, its dissociation constant is 6.25 × 10−5 . If 5 mL of acetic acid is dissolved in 1 litre water, the solution will freeze at −x × 10−2∘C, provided pure water freezes at 0∘C. x = (Kf)water = 1.86 K kg mol−1. density of acetic acid is 1.2 g mol−1. ______ . (Nearest integer) Given : molar mass of water = 18 g mol−1. Acetic acid dissociates as molar mass of acetic acid=60 gmol−1. density of water = 1 g cm−3 CH3COOH ⇌CH3COO⊖+ H⊕

Q55.Total number of aromatic compounds among the following compounds is ______.

Q55.The number of different chain isomers for C7H16 is Q56. 2.5 g of a non-volatile, non-electrolyte is dissolved in 100 g of water at 25∘C. The solution showed a boiling point elevation by 2∘C. Assuming the solute concentration is negligible with respect to the solvent concentration, the vapor pressure of the resulting aqueous solution is mm of Hg (nearest integer) [Given : Molal boiling point elevation constant of water (Kb) = 0.52 K. kgmol−1 , 1 atm pressure = 760 mm of Hg, molar mass of water = 18 g mol−1 ]

Q55.Number of geometrical isomers possible for the given structure is/are _________.