Chemistry questions for JEE Main

An organic compound (P) on treatment with aqueous ammonia under hot condition forms compound (Q) which on heating with Br₂ and KOH forms compound (R) having molecular formula C₆H₇N. Names of P, Q and R respectively are:

Consider the following reaction sequence: Benzene —(conc. HNO₃ + conc. H₂SO₄, 333 K)→ P —(1. Sn/HCl, Δ; 2. pH neutralised)→ Q —((CH₃CO)₂O)→ R —(conc. HNO₃ + conc. H₂SO₄)→ S (major product) —(1. HCl/EtOH, Δ; 2. pH neutralised)→ T The percentage of nitrogen in product 'T' formed is ______ %. (Nearest integer) (Given molar mass in g mol⁻¹: H: 1, C: 12, N: 14, O: 16)

The first and second ionization constants of H₂X are 2.5 × 10⁻⁸ and 1.0 × 10⁻¹³ respectively. The concentration of X²⁻ in 0.1 M H₂X solution is ______ × 10⁻¹⁵ M. (Nearest Integer)

The correct order of the rate of reaction of the following reactants with nucleophile by S_N1 mechanism is: (Given: Structures I and II are rigid) I: 1-bromobicyclo[2.2.2]octane (bridgehead bromide) II: 1-bromobicyclo[2.2.1]heptane (bridgehead bromide of norbornane) III: tert-butyl bromide, (CH₃)₃C–Br IV: trityl bromide, (C₆H₅)₃C–Br

Which of the following mixture gives a buffer solution with pH = 9.25? Given: pK_b(NH₄OH) = 4.75

But-2-yne and hydrogen (one mole each) are separately treated with (i) Pd/C and (ii) Na/liq. NH₃ to give the products X and Y respectively. Identify the incorrect statements. A. X and Y are stereoisomers. B. Dipole moment of X is zero C. Boiling point of X is higher than Y. D. X and Y react with O₃/Zn + H₂O to give different products. Choose the correct answer from the options given below:

The correct stability order of the following diazonium salts is: (A) p-CH₃O–C₆H₄–N₂⁺Cl⁻ (B) p-O₂N–C₆H₄–N₂⁺Cl⁻ (C) C₆H₅–N₂⁺Cl⁻ (D) p-NC–C₆H₄–N₂⁺Cl⁻

The number of possible tripeptides formed involving alanine (ala), glycine (gly) and valine (val), where no amino acid has been used more than once is: