Practice Questions

Q52.Number of molecules/species from the following having one unpaired electron is O2, O−12 , NO, CN−1, O2−2

Q52.Number of compounds / species from the following with non-zero dipole moment is ______ BeCl2, BCl3, NF3, XeF4, CCl4, H2O, H2 S, HBr, CO2, H2, HCl

Q52.Number of molecules having bond order 2 from the following molecules is ________ C2, O2, Be2, Li2, Ne2, N2, He2 Q53. Δvap H⊖ for water is +40.79 kJ mol−1 at 1 bar and 100∘C. Change in internal energy for this vapourisation under same condition is kJmol−1 . (Integer answer) (Given R = 8.3JK−1 mol−1 ) JEE Main 2024 (08 Apr Shift 2) JEE Main Previous Year Paper

Q52.Total number of electrons present in (π∗) molecular orbitals of O2, O2+ and O−2 is _______.

Q52.For a certain reaction at 300 K, K = 10, then ΔG° for the same reaction is – ________ × 10-1 kJ mol-1 . (Given R = 8 . 314JK-1 mol-1)

Q52.The number of species from the following which are paramagnetic and with bond order equal to one is H2, He+2 , O+2 , N2−2 , O2−2 , F2, Ne+2 , B2

Q52.For hydrogen atom, energy of an electron in first excited state is −3.4eV, K. E. of the same electron of hydrogen atom is xeV . Value of x is ______ ×10−1eV . (Nearest integer)

Q52.If IUPAC name of an element is "Unununnium" then the element belongs to nth group of periodic table. The value of n is _______.

Q52.The total number of species from the following in which one unpaired electron is present, is _______ N2, O2, C−2 , O−2 , O2−2 , H+2 , CN−, He+2

Q53.The total number of anti bonding molecular orbitals, formed from 2s and 2p atomic orbitals in a diatomic molecule is _____________.

Q53. Consider the figure provided. 1 mol of an ideal gas is kept in a cylinder, fitted with a piston, at the position A, at 18∘C . If the piston is moved to position B , keeping the temperature unchanged, then ' x ' L atm work is done in this reversible process. x = ______ L atm. (nearest integer) [Given : Absolute temperature = ∘C + 273.15, R = 0.08206 L atm mol−1 K−1 ]

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)

Q53.For the reaction N2O4( g) ⇌2 NO2( g), Kp = 0. 492 atm at 300 K. Kc for the reaction at same temperature is ______ × 10−2 . (Given : R = 0. 082 L atm mol−1 K−1 )

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.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.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 number of species from the following in which the central atom uses sp3 hybrid orbitals in its bonding is _________. NH3, SO2, SiO2, BeCl2, CO2, H2O, CH4, BF3

Q53.When ΔHvap = 30 kJ/mol and ΔSvap = 75 J mol−1 K−1 , then the temperature of vapour, at one atmosphere is ______ K.

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

Q53.Sum of bond order of CO and NO+ is

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.The number of molecules/ion/s having trigonal bipyramidal shape is …….. . PF5, BrF5, PCl5, PtCl4 2 - , BF3, Fe(CO ) 5

Q53.Following Kjeldahl's method, 1 g of organic compound released ammonia, that neutralised 10 mL of 2MH2SO4 . The percentage of nitrogen in the compound is _______ % .

Q53.Three moles of an ideal gas are compressed isothermally from 60 L to 20 L using constant pressure of 5 atm . Heat exchange Q for the compression is - ______ Lit. atm.