Practice Questions

Q29.Two coherent monochromatic light beams of intensities I and 4I are superimposed. The difference between maximum and minimum possible intensities in the resulting beam is xI . The value of x is $_________.

Q29.A parallel beam of monochromatic light of wavelength 5000 A is incident normally on a single narrow slit of width 0 . 001 mm. The light is focused by convex lens on screen, placed on its focal plane. The first minima will be formed for the angle of diffraction of ______ (degree). 𝛼

Q29.In Young's double slit experiment, carried out with light of wavelength 5000\AA, the distance between the slits is 0.3 mm and the screen is at 200 cm from the slits. The central maximum is at x = 0 cm . The value of x for third maxima is _____ mm .

Q30.A nucleus has mass number 𝐴1 and volume 𝑉1. Another nucleus has mass number 𝐴2 and volume 𝑉2. If 𝑉2 relation between mass number is 𝐴2 = 4𝐴1, then = _______. 𝑉1

Q30.An electron of hydrogen atom on an excited state is having energy En = −0. 85 eV. The maximum number of allowed transitions to lower energy level is _______.

Q30.The radius of a nucleus of mass number 64 is 4 . 8 fermi. Then the mass number of another nucleus having radius of 4 fermi is 1000 where 𝑥 is _________. 𝑥,

Q51.The maximum number of orbitals which can be identified with n = 4 and ml = 0 is ______ JEE Main 2024 (04 Apr Shift 2) JEE Main Previous Year Paper

Q51. A hypothetical electromagnetic wave is show below. The frequency of the wave is x × 1019 Hz . x = ______ (nearest integer)

Q51.Volume of 3M NaOH (formula weight 40 g mol-1 ) which can be prepared from 84 g of NaOH is ____ × 10-1dm3. Q52.9 . 3 g of aniline is subjected to reaction with excess of acetic anhydride to prepare acetanilide. The mass of acetanilide produced if the reaction is 100% completed is _____ × 10-1 g. (Given molar mass in g mol-1 N = 14, O = 16, C = 12, H = 1 ) Q53.1 mole of PbS is oxidised by X moles of O3 to get Y moles of O2 . X + Y =

Q51.Mass of methane required to produce 22 g of CO after complete combustion is g. (Given Molar mass in g mol- 1, C = 12. 0, H = 1. 0, O = 16. 0)

Q51.Number of moles of methane required to produce 22g CO2 ( g ) after combustion is x × 10 – 2 moles. The value of x is

Q51.Wavenumber for a radiation having 5800Ã … wavelength is x × 10 cm−1 . The value of x is ________ (Integer answer)

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)

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

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.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.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.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 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 _______.

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.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. 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.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.

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