Practice Questions
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Q51.For hydrogen atom, the orbital/s with lowest energy is/are : (A) 4 s (B) 3px (C) 3 dx2βy2 (D) 3 dz2 (E) 4pz Choose the correct answer from the options given below : (1) (B), (C) and (D) only (2) (A) and (E) only (3) (A) only (4) (B) only
Q51.Concentrated nitric acid is labelled as 75% by mass. The volume in mL of the solution which contains 30 g of nitric acid is ____. Given : Density of nitric acid solution is 1.25 g/mL . (1) 40 (2) 32 (3) 45 (4) 55
Q51.Radius of the first excited state of Helium ion is given as : a0 β radius of first stationary state of hydrogen atom. (1) r = 4a0 (2) r = 2a0 (3) r = a02 (4) r = a04
Q54.Which of the following electronegativity order is incorrect? (1) Mg < Be < B < N (2) S < Cl < O < F (3) Al < Si < C < N (4) Al < Mg < B < N
Q54.Which of the following graphs most appropriately represents a zero order reaction ? 2025 (23 Jan Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)
Q55.Match the LIST-I with LIST-II Choose the correct answer from the options given below: (1) A-IV, B-I, C-III, D-II (2) A-IV, B-II, C-I, D-III (3) A-II, B-IV, C-III, D-I (4) A-III, B-II, C-I, D-IV
Q55.Match List - I with List - II. Choose the correct answer from the options given below : (1) (A)-(I), (B)-(IV), (C)-(III), (D)-(II) (2) (A)-(I), (B)-(II), (C)-(III), (D)-(IV) (3) (A)-(III), (B)-(IV), (C)-(I), (D)-(II) (4) (A)-(III), (B)-(II), (C)-(I), (D)-(IV)
Q55.Total number of nucleophiles from the following is : β NH3, PhSH, (H3C)2 S, H2C = CH2, O H, H3Oβ, (CH3)2CO, βNCH3 (1) 7 (2) 4 (3) 6 (4) 5
Q55. Consider the given figure and choose the correct option : (1) Activation energy of both forward and backward (2) Activation energy of forward reaction is E1 + E2 reaction is E1 + E2 and reactant is more stable and product is less stable than reactant. than product. (3) Activation energy of backward reaction is E1 and (4) Activation energy of forward reaction is E1 + E2 product is more stable than reactant. and product is more stable than reactant.
Q56.Given below are two statements : Statement (I) : NaCl is added to the ice at 0βC, present in the ice cream box to prevent the melting of ice cream. Statement (II) : On addition of NaCl to ice at 0βC, there is a depression in freezing point. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are false (2) Statement I is false but Statement II is true (3) Statement I is true but Statement II is false (4) Both Statement I and Statement II are true
Q57.Preparation of potassium permanganate from MnO2 involves two step process in which the 1st step is a reaction with KOH and KNO3 to produce (1) K3MnO4 (2) K4 [Mn(OH)6] (3) KMnO4 (4) K2MnO4
Q57.In a multielectron atom, which of the following orbitals described by three quantum numbers will have same energy in absence of electric and magnetic fields? A. n = 1, l = 0, m1 = 0 B. n = 2, l = 0, m1 = 0 C. n = 2, l = 1, m1 = 1 D. n = 3, l = 2, m1 = 1 E. n = 3, l = 2, m1 = 0 Choose the correct answer from the options given below: (1) B and C Only (2) A and B Only (3) C and D Only (4) D and E Only
Q57.For bacterial growth in a cell culture, growth law is very similar to the law of radioactive decay. Which of the following graphs is most suitable to represent bacterial colony growth ? Where N - Number of Bacteria at any time, N0 - Initial number of Bacteria. (1) (2) (3) (4)
Q57.Match List - I with List - II : Choose the correct answer from the options given below : (1) (A)-(III), (B)-(II), (C)-(IV), (D)-(I) (2) (A)-(II), (B)-(III), (C)-(IV), (D)-(I) (3) (A)-(III), (B)-(I), (C)-(IV), (D)-(II) (4) (A)-(IV), (B)-(III), (C)-(II), (D)-(I)
Q58.For hydrogen like species, which of the following graphs provides the most appropriate representation of E vs Z plot for a constant n ? [E: Energy of the stationary state, Z : atomic number, n = principal quantum number] (1) (2) (3) (4)
Q59.The Ξ±-Helix and Ξ² - Pleated sheet structures of protein are associated with its : (1) tertiary structure (2) quaternary structure (3) secondary structure (4) primary structure β£β£β£ β£β£β£ β£β£β£ β£β£ 2025 (23 Jan Shift 2) JEE Main Previous Year Paper
Q60. Match List - I with List - II. Choose the correct answer from the options given below : (1) (A)-(II), (B)-(I), (C)-(III), (D)-(IV) (2) (A)-(I), (B)-(II), (C)-(IV), (D)-(III) (3) (A)-(II), (B)-(I), (C)-(IV), (D)-(III) (4) (A)-(II), (B)-(III), (C)-(I), (D)-(IV)
Q60.Which of the following acids is a vitamin? (1) Adipic acid (2) Ascorbic acid (3) Saccharic acid (4) Aspartic acid
Q60.Identify the essential amino acids from below : (A) Valine (B) Proline (C) Lysine (D) Threonine (E) Tyrosine Choose the correct answer from the options given below : (1) (A), (C) and (E) only (2) (A), (C) and (D) only (3) (C), (D) and (E) only (4) (B), (C) and (E) only
Q60.The standard reduction potential values of some of the p-block ions are given below. Predict the one with the strongest oxidising capacity. (1) Eβ = +1.67 V (2) Eβ = +1.15 V Pb4+/Pb2+ Sn4+/Sn2+ (3) Eβ = β1.66 V (4) EβT1/Tl/2.26 V Al3+/Al
Q60.The elemental composition of a compound is 54.2%C, 9.2%H and 36.6%O. If the molar mass of the compound is 132 g molβ1 , the molecular formula of the compound is : [Given : The relative atomic mass of C : H : O = 12 : 1 : 16 ] (1) C4H9O3 (2) C6H12O6 (3) C4H8O2 (4) C6H12O3
Q60.The purification method based on the following physical transformation is : (1) Distillation (2) Extraction (3) Sublimation (4) Crystallization
Q61.Which of the following is/are not correct with respect to energy of atomic orbitals of hydrogen atom? (A) 1 s < 2p < 3 d < 4 s (B) 1 s < 2 s = 2p < 3 s = 3p (C) 1 s < 2 s < 2p < 3 s < 3p (D) 1 s < 2 s < 4 s < 3 d 2025 (28 Jan Shift 2) JEE Main Previous Year Paper Choose the correct answer from the options given below : (1) (A) and (C) only (2) (B) and (D) only (3) (C) and (D) only (4) (A) and (B) only
Q61. Ksp for Cr(OH)3 is 1.6 Γ 10β30 . What is the molar solubility of this salt in water? (1) 1.8Γ10β30 (2) 5β1.8 Γ 10β30 27 Γ 10β30 (3) 4β1.6Γ10β3027 (4) 2β1.6
Q62.Which of the following statement is not true for radioactive decay? (1) Decay constant increases with increase in (2) Amount of radioactive substance remained after temperature. three half lives is 1 th of original amount. 8 (3) Decay constant does not depend upon (4) Half life is ln 2 times of rate constant1 . temperature.