Practice Questions
3,220 questions across 23 years of JEE Main — find and practise any topic!
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Q56.What amount of bromine will be required to convert 2 g of phenol into 2,4,6-tribromophenol? (Given molar mass in gmol−1 of C, H, O, Br are 12, 1, 16, 80 respectively ) (1) 20 .44 g (2) 4.0 g (3) 6.0 g (4) 10.22
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)
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. The compounds which give positive Fehling's test are : (A) (B) (C) HOCH2 −CO −(CHOH)3 −CH2 −OH (D) (E) Choose the correct answer from the options given below : (1) (A), (D) and (E) Only (2) (C), (D) and (E) Only (3) (A), (C) and (D) Only (4) (A), (B) and (C) Only
Q57.The species which does not undergo disproportionation reaction is : (1) ClO−3 (2) ClO− (3) ClO−2 (4) ClO−4
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. E∘Cr2O2−7 /Cr3+ = 1.33 V E∘Cl2/Cl(−) = 1.36 V Based on the data given below : the strongest reducing agent is : E∘ = 1.51 V E∘ = −0.74 V MnO−4 /Mn2+ Cr3+/Cr (1) Cr (2) Cl− (3) MnO−4 (4) Mn2+
Q58.Which of the following electrolyte can be used to obtain H2 S2O8 by the process of electrolysis? (1) Dilute solution of sodium sulphate. (2) Acidified dilute solution of sodium sulphate. (3) Dilute solution of sulphuric acid (4) Concentrated solution of sulphuric acid
Q58.A weak acid HA has degree of dissociation x . Which option gives the correct expression of ( pH pKa )? (1) 0 (2) log(1 + 2x) (3) log ( 1−xx ) (4) log ( 1−xx )
Q58.Standard electrode potentials for a few half cells are mentioned below : E∘ = 0.34 V, E∘ = −0.76 V Cu2+/Cu Zn2+/Zn Which one of the following cells gives the most negative value of E∘Ag+/Ag = 0.80 V, E∘Mg2+/Mg = −2.37 V ΔG∘ ? (1) Zn Zn2+(1M) Ag+(1M) Ag (2) Zn Zn2+(1M) Mg2+(1M) Mg (3) Ag Ag+(1M) Mg2+(1M) Mg (4) Cu Cu2+(1M)∥Ag+(1M) Ag
Q58.The correct set of ions (aqueous solution) with same colour from the following is: 2025 (23 Jan Shift 1) JEE Main Previous Year Paper (1) Sc3+, Ti3+, Cr2+ (2) V2+, Cr3+, Mn3+ (3) Ti4+, V4+, Mn2+ (4) Zn2+, V3+, Fe3+
Q58.The amphoteric oxide among V2O3, V2O4 and V2O5 , upon reaction with alkali leads to formation of an oxide anion. The oxidation state of V in the oxide anion is : (1) +3 (2) +4 (3) +7 (4) +5
Q58. List - I List - II (Carbohydrate) (Linkage Source) (A) Amylose (I) β −C1 −C4, plant Match List - I with List - II. Choose the (B) Cellulose (II) α −C1 −C4, animal (C) Glycogen (III) α −C1 −C4, α −C1 −C6, plant (D) Amylopectin (IV) α −C1 −C4, plant correct answer from the options given below : (1) (A)-(IV), (B)-(I), (C)-(III), (D)-(II) (2) (A)-(III), (B)-(II), (C)-(I), (D)-(IV) (3) (A)-(II), (B)-(III), (C)-(I), (D)-(IV) (4) (A)-(IV), (B)-(I), (C)-(II), (D)-(III)
Q58.The molar solubility(s) of zirconium phosphate with molecular formula (Zr4+)3(PO3−4 )4 is given by relation : (1) Ksp 13 (2) Ksp 17 ( 9612 ) ( 6912 ) (3) Ksp 17 (4) Ksp 16 ( 8435 ) ( 5348 )
Q58.For a reaction, N2O5( g) →2NO2( g) + 12 O2( g) in a constant volume container, no products were present initially. The final pressure of the system when 50% of reaction gets completed is (1) 5 times of initial pressure (2) 5/2 times of initial pressure (3) 7/2 times of initial pressure (4) 7/4 times of initial pressure
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
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 molecules having square pyramidal geometry are (1) BrF5&PCl5 (2) SbF5&PCl5 (3) SbF5&XeOF4 (4) BrF5&XeOF4
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.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.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.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.Arrange the following in increasing order of solubility product : Ca(OH)2, AgBr, PbS, HgS (1) HgS < AgBr < PbS < Ca(OH)2 (2) Ca(OH)2 < AgBr < HgS < PbS (3) PbS < HgS < Ca(OH)2 < AgBr (4) HgS < PbS < AgBr < Ca(OH)2
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.
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+