Practice Questions

Q59.Find the compound ' A ' from the following reaction sequences. A aqua-regia→ B (1) KNO2∣NH4OH→ yellow ppt (2) AcOH (1) CoS (2) ZnS (3) NiS (4) MnS

Q59.The α-Helix and β - Pleated sheet structures of protein are associated with its : (1) tertiary structure (2) quaternary structure (3) secondary structure (4) primary structure ∣∣∣ ∣∣∣ ∣∣∣ ∣∣ 2025 (23 Jan Shift 2) JEE Main Previous Year Paper

Q59.Which one of the following reaction sequences will give an azo dye? 2025 (29 Jan Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)

Q59.Identify the homoleptic complex(es) that is/are low spin. (A) [Fe(CN)5NO]2− (B) [CoF6]3− (C) [Fe(CN)6]4− (D) [Co(NH3)6]3+ (E) [Cr(H2O)6]2+ Choose the correct answer from the options given below : (1) (C) only (2) (C) and (D) only (3) (A) and (C) only (4) (B) and (E) only 2025 (22 Jan Shift 2) JEE Main Previous Year Paper

Q59.The molar conductivity of a weak electrolyte when plotted against the square root of its concentration, which of the following is expected to be observed ? (1) A small decrease in molar conductivity is (2) Molar conductivity decreases sharply with observed at infinite dilution. increase in concentration. (3) A small increase in molar conductivity is (4) Molar conductivity increases sharply with observed at infinite dilution. increase in concentration.

Q59.Given below are two statements : Statement I : CH3 −O −CH2 −Cl will undergo SN1 reaction though it is a primary halide. Statement II : will not undergo SN2 reaction very easily though it is a primary halide. In the light of the above statements, choose the most appropriate answer from the options given below : (1) Both Statement I and Statement II are incorrect (2) Both Statement I and Statement II are correct (3) Statement I is incorrect but Statement II is (4) Statement I is correct but Statement II is correct incorrect

Q59.Given below are two statements: Statement I: In Lassaigne's test, the covalent organic molecules are transformed into ionic compounds. Statement II: The sodium fusion extract of an organic compound having N and S gives prussian blue colour with FeSO4 and Na4 [Fe(CN)6] In the light of the above statements, choose the correct answer from the options given below. (1) Statement I is true but Statement II is false (2) Both Statement I and Statement II are false (3) Both Statement I and Statement II are true (4) Statement I is false but Statement II is true

Q59.One mole of the octahedral complex compound Co(NH3)5Cl3 gives 3 moles of ions on dissolution in water. One mole of the same complex reacts with excess of AgNO3 solution to yield two moles of AgCl(s) . The structure of the complex is: (1) [Co(NH3)4Cl2] ⋅Cl ⋅NH3 (2) [Co(NH3)3Cl3] ⋅2NH3 (3) [Co(NH3)5Cl]Cl2 (4) [Co(NH3)4Cl] ⋅Cl2 ⋅NH3

Q60.Consider the following elements In, Tl, Al, Pb, Sn and Ge . The most stable oxidation states of elements with highest and lowest first ionisation enthalpies, respectively, are (1) +4 and +1 (2) +1 and +4 (3) +4 and +3 (4) +2 and +3 2025 (28 Jan Shift 1) JEE Main Previous Year Paper

Q60.Which of the following ions is the strongest oxidizing agent? (Atomic Number of Ce = 58, Eu = 63, Tb = 65, Lu = 71 ) 2025 (24 Jan Shift 1) JEE Main Previous Year Paper (1) Eu2+ (2) Tb4+ (3) Lu3+ (4) Ce3+

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) E⊖ = +1.67 V (2) E⊖ = +1.15 V Pb4+/Pb2+ Sn4+/Sn2+ (3) E⊖ = −1.66 V (4) E⊖T1/Tl/2.26 V Al3+/Al

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.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.Given below are the atomic numbers of some group 14 elements. The atomic number of the element with lowest melting point is : (1) 6 (2) 82 (3) 14 (4) 50

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 mol−1 , 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.Propane molecule on chlorination under photochemical condition gives two di-chloro products, " x " and " y ". Amongst " x " and " y ", " x " is an optically active molecule. How many tri-chloro products (consider only structural isomers) will be obtained from " x " when it is further treated with chlorine under the photochemical condition? (1) 2 (2) 5 (3) 4 (4) 3

Q60.The purification method based on the following physical transformation is : (1) Distillation (2) Extraction (3) Sublimation (4) Crystallization

Q60.Which of the following acids is a vitamin? (1) Adipic acid (2) Ascorbic acid (3) Saccharic acid (4) Aspartic acid

Q61.The product (P) formed in the following reaction is : (1) (2) (3) (4) 2025 (29 Jan Shift 1) JEE Main Previous Year Paper

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.The conditions and consequence that favours the t2ggeg1 configuration in a metal complex are (1) weak field ligand, low spin complex (2) weak field ligand, high spin complex (3) strong field ligand, high spin complex (4) strong field ligand, low spin complex

Q61.Match List-I with List-II. List −I cList −II (A) Al3+ < Mg2+ < Na+ < F− (I) IonisationEnthalpy (B) B < C < O < N (II) Metalliccharacter (C) B < Al < Mg < K (III) Electronegativity (D) Si < P < S < Cl (IV ) Ionicradii 2025 (22 Jan Shift 1) JEE Main Previous Year Paper Choose the correct answer from the options given below : (1) (A)-(IV), (B)-(I), (C)-(II), (D)-(III) (2) (A)-(IV), (B)-(I), (C)- (III), (D)-(II) (3) (A)-(III), (B)-(IV), (C)- (II), (D)-(I) (4) (A)-(II), (B)-(III), (C)-(IV), (D)-(I)

Q61. For a given reaction R →P, t1/2 is related to [A]0 as given in table. Given: log 2 = 0.30 Which of the following is true? A. The order of the reaction is 1/2. B. If [A]0 is 1 M , then t1/2 is 200√10 min C. The order of the reaction changes to 1 if the concentration of reactant changes from 0.100 M to 0.500 M . D. t1/2 is 800 min for [A]0 = 1.6M Choose the correct answer from the options given below: Options (1) A and C Only (2) A, B and D Only (3) C and D Only (4) A and B Only

Q61. Ksp for Cr(OH)3 is 1.6 × 10−30 . What is the molar solubility of this salt in water? (1) 1.8×10−30 (2) 5√1.8 × 10−30 27 × 10−30 (3) 4√1.6×10−3027 (4) 2√1.6

Q61.Identify the number of structure/s from the following which can be correlated to D-glyceraldehyde. (1) four (2) one (3) two (4) three