Practice Questions
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Q53.The pH of an aqueous solution containing 1M benzoic acid pKa = 4 . 20 and 1M sodium benzoate is 4 . 5 . The volume of benzoic acid solution in 300 mL of this buffer solution is __________mL.
Q53.Sum of bond order of CO and NO+ is
Q53.When equal volume of 1MHCl and 1MH2SO4 are separately neutralised by excess volume of 1M NaOH solution. x and y kJ of heat is liberated respectively. The value of y/x is _______
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.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
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.If 5 moles of an ideal gas expands from 10L to a volume of 100L at 300K under isothermal and reversible condition then work, w, is −x J. The value of x is - _______. (Given R = 8 .314 J K-1 mol-1)
Q54.Total number of species from the following which can undergo disproportionation reaction ___________. H2O2, ClO3- , P4, Cl2, Ag, Cu+1, F2, NO2, K+
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.Number of isomeric products formed by monochlorination of 2-methylbutane in presence of sunlight is _______.
Q54. The number of optical isomers in following compound is: ________
Q54.Total number of optically active compounds from the following is ______
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.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.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 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.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.Total number of isomeric compounds (including stereoisomers) formed by monochlorination of 2- methylbutane is ______.
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)
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−]
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. Consider the given reaction. The total number of oxygen atoms present per molecule of the product (P) is _________.
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 ______.