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Consider the reaction sequence from P to Q shown below. The overall yield of the major product Q from P is 75%. What is the amount in grams of Q obtained from 9.3 mL of P? (Use density of P = 1.00 g mL⁻¹; Molar mass of C = 12.0, H =1.0, O =16.0 and N = 14.0 g mol⁻¹)

Answer: 18.6 Molecular weight of aniline (C6H5NH2) = 77 + 14 + 2 = 93 Density of P = 1 gm ml–1 d = m/v or m = dv Mass of P = 9.3... View Article

The figure below is the plot of potential energy versus internuclear distance ( ) of H₂ molecule in the electronic ground state. What is the value of the net potential energy ₀ (as indicated in the figure) in kJ mol⁻¹, for = ₀ at which the electron-electron repulsion and the nucleus-nucleus repulsion energies are absent? As reference, the potential energy of H atom is taken as zero when its electron and the nucleus are infinitely far apart.

Use Avogadro constant as 6.023 × 1023 mol−1. Answer: –5242.42 P. E of 2 H-atoms Total eng = P.E./2 Potential Energy = 2... View Article

Liquids A and B form ideal solution for all compositions of A and B at 25℃. Two such solutions with 0.25 and 0.50 mole fractions of A have the total vapor pressures of 0.3 and 0.4 bar, respectively. What is the vapor pressure of pure liquid B in bar?

Answer: 0.2 PTotal = 0.3, where xA = xA + xB = 1 ⇒ xB = 0.75 = ⇒ 0.3= + …(1) PTotal = 0.4 where xA=, xB =... View Article

A solution of 0.1 M weak base (B) is titrated with 0.1 M of a strong acid (HA). The variation of pH of the solution with the volume of HA added is shown in the figure below. What is the p b of the base? The neutralization reaction is given by

B + HA → BH+ + A−. Answer: 3.3 kb = 5 × 10–4 pkb = –logkb = –log(5 × 10–4) =... View Article

Consider the following transformations of a compound P.

Answer: B, C • NaNH2 acts as a base for the double elimination of geminal or vicinal dihalides to give alkynes. • Pd-C /... View Article

Consider the following four compounds I, II, III, and IV.

Choose the correct statement(s). a) The order of basicity is II >I >III >IV. b) The magnitude of pKb difference between I and II is... View Article

Choose the correct statement(s) among the following.

a) SnCl2.2H2O is a reducing agent. b) SnO2 reacts with KOH to form K2[Sn(OH)6]. c) A solution of PbCl2 in HCl contains Pb2+and Cl−ions.... View Article

Which among the following statement(s) is(are) true for the extraction of aluminium from bauxite?

a) Hydrated Al2O3 precipitates, when CO2 is bubbled through a solution of sodium aluminate. b) Addition of Na3AlF6 lowers the melting point of... View Article

Which of the following plots is (are) correct for the given reaction?

([P]0 is the initial concentration of P) Answer: A As there is no inversion. Hence should be SN1 → 1st order c) x = a{1... View Article

in an experiment m grams of a compound x gas liquid or solid taken in a container is loaded in a balance

a) If X is H2O(l), deflection of the panis upwards. b) If X is K4[Fe(CN)6]( ), deflection of the panis upwards. c) If X is O2 ( ), deflection of... View Article

An organic compound (C₈H₁₀O₂) rotates plane-polarized light. It produces pink color with neutral FeCl₃ solution. What is the total number of all the possible isomers for this compound?

Answer: 6 DBE (Double bond equivalent) of C8H10O2 is = Number of carbon atoms – (Number of monovalent atoms)/2 + 1 = 8 – 10/2 + 1... View Article

The structure of a peptide is given below.

If the absolute values of the net charge of the peptide at pH = 2, pH = 6, and pH = 11 are | 1|, | 2|, and | 3|, respectively, then what is |... View Article

An acidified solution of potassium chromate was layered with an equal volume of amyl alcohol. When it was shaken after the addition of 1 mL of 3% H₂O₂, a blue alcohol layer was obtained. The blue color is due to the formation of a chromium (VI) compound ‘X’. What is the number of oxygen atoms bonded to chromium through only single bonds in a molecule of X

Answer: 4 Blue colour compound of 'Cr' is CrO5. Oxygen atoms bonded to chromium through only single bonds = 4... View Article

In the chemical reaction between stoichiometric quantities of KMnO₄ and KI in weakly basic solution, what is the number of moles of I₂ released for 4 moles of KMnO₄ consumed?
Answer: 6 Chemical reaction of KMnO4 and KI in weakly basic solution is given as Equivalents of KMnO4= Equivalents of I2 n-factor ×... View Article

Consider the following compounds in the liquid form: O₂, HF, H₂O, NH₃, H₂O₂, CCl₄, CHCl₃, C₆H₆, C₆H₅Cl. When a charged comb is brought near their flowing stream, how many of them show deflection as per the following figure?
Answer: 6 Only polar molecules are deflected by charged comb. Polar molecules: HF, H2O, NH3, H2O2, CHCl3, C6H5Cl Non-polar molecules: O2,... View Article

The 1^st, 2^nd, and the 3^rd ionization enthalpies, ₁, ₂, and ₃, of four atoms with atomic numbers n, + 1, + 2, and + 3, where < 10, are tabulated below. What is the value of n?
Atomic Number Ionization Enthalpy (kJ/mol) I1 I2 I3 n 1681 3374 6050 n+1... View Article

Consider the compound A [Cr (H₂O)₆] Cl₃ ; yellow B [Cr(NH₃)₆] Cl₃ violet. Then which of the following is incorrect.
a) (Δ0)A< (Δ0)B b) The crystal field splitting parameter can be measured by wavelengths of complementary colors for (A) and (B) respectively.... View Article

Choose the correct option from the image given below:
Answer (1)... View Article

Write the product of given reaction:
Answer (1) It involves nucleophilic substitution reaction (SN2 ) followed by oxidation with oxidising agent and removal of water molecule.... View Article

Arrange the following amino acids in order of their PKa order.
Lysine, Aspartic acid, Arginine, Glycine. a) lys > Arg > Gly > Asp b) Arg > Lys > Asp > Gly c) Gly > Asp > Arg >... View Article

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