Practice Questions

Q53.The total number of molecular orbitals formed from 2s and 2p atomic orbitals of a diatomic molecule

Q53.When ΔHvap = 30 kJ/mol and ΔSvap = 75 J mol−1 K−1 , then the temperature of vapour, at one atmosphere is ______ 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.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.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.Using the given figure, the ratio of Rf values of sample A and sample C is x × 10−2 . Value of x is ______

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

Q54.Total number of species from the following which can undergo disproportionation reaction ___________. H2O2, ClO3- , P4, Cl2, Ag, Cu+1, F2, NO2, 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.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.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.Number of isomeric products formed by monochlorination of 2-methylbutane in presence of sunlight is _______.

Q54.Standard enthalpy of vapourisation for CCl4 is 30. 5 kJ mol−1 . Heat required for vapourisation of 284 g of CCl4 at constant temperature is __________ kJ. (Given molar mass in gmol−1; C = 12, Cl = 35. 5) Round off your answer to the nearest integer.

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.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.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 isomeric compounds (including stereoisomers) formed by monochlorination of 2- methylbutane 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]

Q54.Total number of optically active compounds from the following 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.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 _______.

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

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.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−]