Practice Questions
3,220 questions across 23 years of JEE Main — find and practise any topic!
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Q66.When sec-butylcyclohexane reacts with bromine in the presence of sunlight, the major product is : (1) (2) (3) (4)
Q67.The most stable carbocation from the following is : 2025 (22 Jan Shift 2) JEE Main Previous Year Paper (1) (2) (3) (4)
Q67.For the given cell Fe2+ (aq) + Ag+ (aq) →Fe3+(aq) + Ag(s) The standard cell potential of the above reaction is Ag+ + e−→Ag Eθ = xV Given: Fe2+ + 2e−→Fe Eθ = yV Fe3+ + 3e−→Fe Eθ = zV (1) x + y −z (2) x + 2y (3) x + 2y −3z (4) y −2x
Q67.The successive 5 ionisation energies of an element are 800, 2427, 3658, 25024 and 32824 kJ/mol, respectively. By using the above values predict the group in which the above element is present : (1) Group 13 (2) Group 14 (3) Group 2 (4) Group 4 2025 (24 Jan Shift 2) JEE Main Previous Year Paper
Q67. Choose the correct answer from the options given below : (1) (A)-(I), (B)-(IV), (C)-(III), (D)-(II) (2) (A)-(III), (B)-(II), (C)-(I), (D)-(IV) (3) (A)-(III), (B)-(IV), (C)-(I), (D)-(II) (4) (A)-(II), (B)-(III), (C)-(I), (D)-(IV)
Q67.Match the 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-II, B-III, C-I, D-IV (3) A-IV, B-I, C-III, D-II (4) A-IV, B-III, C-I, D-II
Q67. The IUPAC name of the following compound is : (1) Methyl-6-carboxy-2,5-dimethylhexanoate. (2) 2-Carboxy-5-methoxycarbonylhexane. (3) 6-Methoxycarbonyl-2,5-dimethylhexanoic acid. (4) Methyl-5-carboxy-2-methylhexanoate.
Q68.In which of the following complexes the CFSE, Δo will be equal to zero? (1) [Fe(en)3]Cl3 (2) K4 [Fe(CN)6] (3) [Fe(NH3)6]Br2 (4) K3 [Fe(SCN)6]
Q68.For a Mg Mg2+(aq) Ag+(aq) Ag the correct Nernst Equation is : [Ag+] [Ag+]2 (1) (2) Ecell = Eocell −RT2 F ln [Mg2+] Ecell = Eocell + RT2 F ln [Mg2+] (3) [Ag+]2 (4) [Mg2+] cell −RT2 F ln [Ag+] Ecell = Eocell −RT2 F ln [Mg2+] Ecell = Eo
Q68.Identify the inorganic sulphides that are yellow in colour : (A) (NH4)2 S (B) Pbs (C) Cus (D) As2 S3 (E) As2 S5 Choose the correct answer from the options given below : (1) (A), (D) and (E) only (2) (D) and (E) only (3) (A) and (B) only (4) (A) and (C) only
Q68.pH of water is 7 at 25∘C. If water is heated to 80∘C., it's pH will : (1) Decrease (2) H+ concentration increases, OH− concentration decreases (3) Remains the same (4) Increase 2025 (23 Jan Shift 2) JEE Main Previous Year Paper
Q68.Match the Compounds (List - I) with the appropriate Catalyst/Reagents (List - II) for their reduction into corresponding amines. Choose the correct answer from the options given below : (1) (A)-(II), (B)-(I), (C)-(III), (D)-(IV) (2) (A)-(III), (B)-(II), (C)-(IV), (D)-(I) (3) (A)-(II), (B)-(IV), (C)-(III), (D)-(I) (4) (A)-(III), (B)-(IV), (C)-(II), (D)-(I)
Q69.Which of the following mixing of 1 M base and 1 M acid leads to the largest increase in temperature? (1) 30 mLCH3COOH and 30 mL NaOH (2) 45mLCH3COOHand25mLNaOH (3) 30 mL HCl and 30 mL NaOH (4) 50 mL HCl and 20 mL NaOH 2025 (24 Jan Shift 2) JEE Main Previous Year Paper Q70. 3 S( g) + O2( g) →SO3( g) + 2xkcal 2 The heat of formation of SO2( g) is given by : 1 SO2( g) + O2( g) →SO3( g) + ykcal 2 (1) x + ykcal (2) y −2xkcal (3) 2x y kcal (4) 2x + ykcal
Q69.Identify the coordination complexes in which the central metal ion has d4 configuration. Choose the correct answer from the options given below : (1) (B), (C) and (D) only (2) (C) and (E) only (3) (B) and (D) only (4) (A), (B) and (E) only
Q69.The major product of the following reaction is : (1) 2-Phenylhepta-2,5-diene (2) 6-Phenylhepta-2,4-diene (3) 6-Phenylhepta-3,5-diene (4) 2-Phenylhepta-2,4-diene
Q69.The d- electronic configuration of an octahedral Co(II) complex having magnetic moment of 3.95 BM is: (1) t2 g3eg0 (2) t2 g6eg1 (3) t2 g5eg2 (4) e4t23 2025 (23 Jan Shift 1) JEE Main Previous Year Paper
Q69.Arrange the following compounds in increasing order of their dipole moment : HBr, H2 S, NF3 and CHCl3 (1) H2 S < HBr < NF3 < CHCl3 (2) NF3 < HBr < H2 S < CHCl3 (3) HBr < H2 S < NF3 < CHCl3 (4) CHCl3 < NF3 < HBr < H2 S
Q69.The incorrect decreasing order of atomic radii is (1) Si > P > Cl > F (2) Be > Mg > Al > Si (3) Al > B > N > F (4) Mg > Al > C > O
Q69.Arrange the following solutions in order of their increasing boiling points. (i) 10−4M NaCl (ii) 10−4M Urea (iii) 10−3M NaCl (iv) 10−2M NaCl (1) (i) < (ii) < (iii) < (iv) (2) (iv) < (iii) < (i) < (ii) (3) (ii) < (i ) ≡(iii) < (iv) (4) (ii) < (i) < (iii) < (iv)
Q69. In the following substitution reaction: product ′P′ formed is : (1) (2) (3) (4)
Q70.When a non-volatile solute is added to the solvent, the vapour pressure of the solvent decreases by 10 mm of Hg . The mole fraction of the solute in the solution is 0.2 . What would be the mole fraction of the solvent if decrease in vapour pressure is 20 mm of Hg ? (1) 0.8 (2) 0.4 (3) 0.2 (4) 0.6 Q71.0.01 mole of an organic compound (X) containing 10% hydrogen, on complete combustion produced 0.9 gH2O. Molar mass of (X) is _____ gmol−1 .
Q70.Identify correct conversion during acidic hydrolysis from the following : (A) starch gives galactose. (B) cane sugar gives equal amount of glucose and fructose. (C) milk sugar gives glucose and galactose. (D) amylopectin 2025 (28 Jan Shift 2) JEE Main Previous Year Paper gives glucose and fructose. (E) amylose gives only glucose. Choose the correct answer from the options given below : (1) (A), (B) and (C) only (2) (B), (C) and (E) only (3) (C), (D) and (E) only (4) (B), (C) and (D) only
Q70.The correct increasing order of stability of the complexes based on Δo value is : I. [Mn(CN)6]3− II. [Co(CN)6]4− III. [Fe(CN)6]4− IV. [Fe(CN)6]3− (1) IV < III < II < I (2) I < II < IV < III (3) III < II < IV < I (4) II < III < I < IV
Q70.From the magnetic behaviour of [NiCl4]2− (paramagnetic) and [Ni(CO)4] (diamagnetic), choose the correct geometry and oxidation state. (1) [NiCl4]2−: NiII , tetrahedral [Ni(CO)4] : NiII , (2) [NiCl4]2− : NiII , square planar [Ni(CO)4] : Ni(0) square planar , square planar (3) [NiCl4]2−: NiII , tetrahedral [Ni(CO)4] : Ni(0), (4) [NiCl4]2−: Ni(0), tetrahedral [Ni(CO)4] : Ni(0), tetrahedral square planar
Q70.The maximum covalency of a non-metallic group 15 element ' E ' with weakest E −E bond is : (1) 4 (2) 6 (3) 3 (4) 5