Practice Questions

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

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

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

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

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

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 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.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.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.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.The amount of electricity in Coulomb required for the oxidation of 1 mol of H2O to O2 is ______ × 105C .

Q56.Time required for 99.9% completion of a first order reaction is _______ times the time required for completion of 90% reaction.(nearest integer)

Q56.Among VO+2 , MnO−4 and Cr2O2−7 , the spin-only magnetic moment value of the species with least oxidising ability is ______ BM (Nearest integer). (Given atomic member V = 23, Mn = 25, Cr = 24) JEE Main 2024 (06 Apr Shift 2) JEE Main Previous Year Paper

Q56.For a certain thermochemical reaction M →N at T = 400 K, ΔHo = 77 . 2 kJ mol-1, ΔSo = 122JK-1, log equilibrium constant ( logK ) is - _____ × 10-1.

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.The standard reduction potentials at 298 K for the following half cells are given below : Cr2O2−7 + 14H+ + 6e−→2Cr3+ + 7H2O, E∘= 1.33 V Fe3+(aq) + 3e−→Fe E∘= −0.04 V Ni2+(aq) + 2e−→Ni E∘= −0.25 V Consider the given electrochemical reactions, The Ag+(aq) + e−→Ag E∘= 0.80 V Au3+(aq) + 3e−→Au E∘= 1.40 V number of metal(s) which will be oxidized be Cr2O2−7 , in aqueous solution is ______

Q56.NO2 required for a reaction is produced by decomposition of N2O5 in CCl4 as by equation 2N2O5 ( g ) →4NO2 ( g ) + O2 ( g ) The initial concentration of N2O5 is 3 mol L-1 and it is 2 . 75 mol L-1 after 30 minutes. The rate of formation of NO2 is x × 10-3 mol L-1 min-1, value of x is ________.

Q56.A solution is prepared by adding 1 mole ethyl alcohol in 9 mole water. The mass percent of solute in the solution is ________ (Integer answer) (Given : Molar mass in gmol−1 Ethyl alcohol : 46 water: 18)

Q56.Among the given organic compounds, the total number of aromatic compounds is JEE Main 2024 (27 Jan Shift 1) JEE Main Previous Year Paper Q57. 3−Methylhex-2-ene on reaction with HBr in presence of peroxide forms an addition product (A). The number of possible stereoisomers for ' A ' is ________.