Practice Questions

Q18.The mass number of nucleus having radius equal to half of the radius of nucleus with mass number 192 is: (1) 24 (2) 32 (3) 40 (4) 20

Q19.A light emitting diode (LED) is fabricated using GaAs semiconducting material whose band gap is 1.42eV. The wavelength of light emitted from the LED is : (1) 1400 nm (2) 650 nm (3) 875 nm (4) 1243 nm

Q19.An electron rotates in a circle around a nucleus having positive charge Ze. Correct relation between total energy (E) of electron to its potential energy (U) is : (1) E = U (2) 2E = U (3) 2E = 3U (4) E = 2U

Q19. Identify the logic gate given in the circuit: (1) NAND-gate (2) AND gate (3) NOR gate (4) OR- gate

Q19.The I −V characteristics of an electronic device shown in the figure. The device is: (1) a diode which can be used as a rectifier (2) a zener diode which can be used as a voltage regulator (3) a transistor which can be used as an amplifier (4) a solar cell

Q19.The output (Y ) of logic circuit given below is 0 only when : (1) A = 1, B = 0 (2) A = 0, B = 1 (3) A = 0, B = 0 (4) A = 1, B = 1

Q19.The ratio of the magnitude of the kinetic energy to the potential energy of an electron in the 5th excited state of a hydrogen atom is : (1) 4 (2) 14 (3) 1 (4) 1 2

Q19.Which of the following circuits is reverse - biased ? (1) (2) (3) (4)

Q20.The value of net resistance of the network as shown in the given figure is : (1) 6Ω (2) (5/2)Ω (3) (15/4)Ω (4) (30/11)Ω

Q20.If 50 Vernier divisions are equal to 49 main scale divisions of a travelling microscope and one smallest reading of main scale is 0 . 5 mm the Vernier constant of travelling microscope is: (1) 0 . 1 mm (2) 0 . 1 cm (3) 0 . 01 cm (4) 0 . 01 mm → →

Q21.A particle is moving in one dimension (along 𝑥 axis) under the action of a variable force. It's initial position was 16 m right of origin. The variation of its position 𝑥 with time 𝑡 is given as 𝑥= – 3𝑡3 + 18𝑡2 + 16𝑡, where 𝑥 is in m and 𝑡 is in s . The velocity of the particle when its acceleration becomes zero is _________ m s-1 . JEE Main 2024 (01 Feb Shift 1) JEE Main Previous Year Paper

Q31.Combustion of glucose (C6H12O6) produces CO2 and water. The amount of oxygen (in g) required for the complete combustion of 900 g of glucose is : [Molar mass of glucose in gmol−1 = 180 ] (1) 480 (2) 800 (3) 960 (4) 32

Q31.The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency ' A ' ×1012 hertz and that has a radiant intensity in that direction of ′ 1B′ watt per steradian. 'A' and 'B' are respectively (1) 540 and 683 (2) 450 and 683 (3) 450 and 1 (4) 540 and 1 683 683

Q31.The number of radial node/s for 3p orbital is: (1) 1 (2) 4 (3) 2 (4) 3

Q31.Compare the energies of following sets of quantum numbers for multielectron system. (A) n = 4, 1 = 1 (B) n = 4, l = 2 (C) n = 3, 1 = 1 (D) n = 3, 1 = 2 (E) n = 4, 1 = 0 Choose the correct answer from the options given below : (1) (B) > (A) > (C) > (E) > (D) (2) (E) < ( C ) < (D) < ( A ) < ( B ) (3) (E) > ( C ) > ( A ) > ( D ) > (B) (4) (C) < (E) < (D) < (A) < (B)

Q31.The number of moles of methane required to produce 11 gCO2( g) after complete combustion is : (Given molar mass of methane in gmol−1 : 16) (1) 0.35 (2) 0.5 (3) 0.75 (4) 0.25

Q31.The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is: (1) 5, 0, 0, + 12 (2) 5, 0, 1, + 12 (3) 5, 1, 0, + 12 (4) 5, 1, 1, + 12

Q31.The electronic configuration for Neodymium is: [Atomic Number for Neodymium 60] JEE Main 2024 (27 Jan Shift 1) JEE Main Previous Year Paper (1) [Xe] 4f 4 6s2 (2) [Xe] 5f 47s2 (3) [Xe] 4f 6 6s2 (4) [Xe] 4f 15d16s2

Q32.The four quantum numbers for the electron in the outer most orbital of potassium (atomic no. 19) are (1) n = 4, l = 2, m = −1, s = + 1 (2) n = 4, l = 0, m = 0, s = + 1 2 2 1 1 (3) n = 3, l = 0, m = −1, s = + (4) n = 2, l = 0, m = 0, s = + 2 2

Q32.The molecular formula of second homologue in the homologous series of mono carboxylic acids is _________. (1) C3H6O2 (2) C2H4O2 (3) CH2O (4) C2H2O2

Q32.Which of the following electronic configuration would be associated with the highest magnetic moment ? (1) [Ar] 3d7 (2) [Ar] 3d8 (3) [Ar] 3d3 (4) [Ar] 3d6

Q32.The shape of carbocation is : (1) diagonal pyramidal (2) trigonal planar (3) tetrahedral (4) diagonal

Q32.The ratio KP for the reaction : CO(g) + 12 O2( g) ⇌CO2( g) is : KC (1) 1 (2) (RT)1/2 √RT (3) RT (4) 1

Q32.The incorrect postulates of the Dalton's atomic theory are : (A) Atoms of different elements differ in mass. (B) Matter consists of divisible atoms. (C) Compounds are formed when atoms of different element combine in a fixed ratio. (D) All the atoms of given element have different properties including mass. (E) Chemical reactions involve reorganisation of atoms. Choose the correct answer from the options given below : (1) (C), (D), (E) only (2) (B), (D) only (3) (A), (B), (D) only (4) (B), (D), (E) only

Q32.In case of isoelectronic species the size of F–, Ne and Na+ is affected by: (1) Principal quantum number n (2) None of the factors because their size is the same (3) Electron-electron interaction in the outer orbitals (4) Nuclear charge z