Practice Questions

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

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

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

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.The values of conductivity of some materials at 298 .15 K in Sm−1 are 2 .1 × 103, 1 .0 × 10−16, 1 .2 × 10, 3 .91 , 1 .5 × 10−2, 1 × 10−7, 1 .0 × 103. The number of conductors among the materials 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 ______.

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

Q55. Consider the given reaction. The total number of oxygen atoms present per molecule of the product (P) 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.The number of non-polar molecules from the following is HF, H2O, SO2, H2, CO2, CH4, NH3, HCl, CHCl3, BF3

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

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

Q55.Consider the dissociation of the weak acid HX as given below HX(aq) ⇌H+(aq) + X−(aq), Ka = 1.2 × 10−5 [Ka : dissociation constant ] The osmotic pressure of 0.03M aqueous solution of HX at 300 K is _______ ×10−2 bar (nearest integer). [Given : R = 0.083 Lbarmol−1 K−1 ]

Q56.Total number of deactivating groups in aromatic electrophilic substitution reaction among the following is JEE Main 2024 (01 Feb Shift 1) JEE Main Previous Year Paper

Q56.If 50 mL of 0. 5M oxalic acid is required to neutralise 25 mL of NaOH solution, the amount of NaOH in 50 mL of given NaOH solution is_______g. JEE Main 2024 (29 Jan Shift 2) JEE Main Previous Year Paper

Q56.Consider the following reaction A + B →C The time taken for A to become 1/4th of its initial concentration is twice the time taken to become 1/2 of the same. Also, when the change of concentration of B is plotted against time, the resulting graph gives a straight JEE Main 2024 (08 Apr Shift 1) JEE Main Previous Year Paper line with a negative slope and a positive intercept on the concentration axis. The overall order of the reaction is _______

Q56.Consider the following single step reaction in gas phase at constant temperature. 2 A(g) + B(g) →C(g) The initial rate of the reaction is recorded as r1 when the reaction starts with 1.5 atm pressure of A and 0.7 atm pressure of B . After some time, the rate r2 is recorded when the pressure of C becomes 0.5 atm. The ratio r1 : r2 is ______ ×10−1 . (Nearest integer) JEE Main 2024 (05 Apr Shift 2) JEE Main Previous Year Paper

Q56.The vapour pressure of pure benzene and methyl benzene at 27∘C is given as 80 Torr and 24 Torr, respectively. The mole fraction of methyl benzene in vapour phase, in equilibrium with an equimolar mixture of those two liquids (ideal solution) at the same temperature is _______ ×10−2 (nearest integer)

Q56.A solution of H2 SO4 is 31. 4% H2 SO4 by mass and has a density of 1. 25 g/ mL. The molarity of the H2 SO4 solution is M (nearest integer) [Given molar mass of H2 SO4 = 98 g mol−1 ]