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Solution of 100 ml water contains 0.73 g of Mg(HCO₃)₂ and 0.81 g of Ca(HCO₃)₂. Calculate the hardness in terms of ppm of CaCO₃

a. 102 ppm b. 104 ppm c. 5 × 103 ppm d. 103 ppm Answer: (c) Number of moles of Number of moles of .... View Article

A forms ccp lattice, B occupy half of the octahedral voids and ‘O’ occupy all the tetrahedral voids. Calculate formula –

a. A2BO4 b. ABO4 c. A2B2O d. A2B2O Answer: (a) CCP lattice of A → no of atom of A per unit cell → 4. N oct. voids = 2 N tetra.Voids. But... View Article

Arrange the following set of quantum numbers having highest energy of an electron.

(p) n = 4 l = 1 m = +1 (q) n = 4 l = 2 m = -1 s (r) n = 3 l = 2 m = 0 s (s) n = 3 l = 1 m + 1 s a. q > r > p > s b. q... View Article

In a mixture of A and B having vapour pressure of pure A and pure B are 400 mm Hg and 600 mm Hg respectively, mole fraction of B in liquid phase is 0.5. Calculate total vapour pressure and mole fraction of A and B in vapour phase

a.500, 0.4, 0.6 b.500, 0.5, 0.5 c.450, 0.4, 0.6 d.450, 0.5, 0.5 Answer : (a) = 0. 5 × 400 + 0.5 × 600 = 500 mm of Hg... View Article

In Freundlich isotherm, [latex]frac{x}{m}propto {{P}^{a}}.[/latex] Find the value of a from the following graph

a. b. c. d. 1 Answer : (a) Freundlich Isotherm equations:... View Article

Which of the following is not correct for an ideal gas as per first law of thermodynamics

a. Adiabatic ΔU = -w b. Isothermal q = -w c. cyclic q = -w d. Isochoric ΔU = q Answer: (a) From 1st Law, ∆U = q + ω In adiabatic, q = 0... View Article

Find the compound ‘X’ which gives the following test.

Neutral FeCl3 -ve Fehling solution -ve Iodoform reaction +ve Grignard reagent +ve Answer: (a) Neutre Fecl3 → - ve (phenol... View Article

Which is the correct option for the following reaction:

Answer: (c) In a2o coupling reaction, the Hydrogen is taken from the less hindered para position.... View Article

Choose the correct option for the following reaction:

Answer: (a) Two reaction occur simultaneously a) Ether hydrolysis using HBr b) Electrophilic addition of H-Br... View Article

X will be:

X will be: Answer: (c)... View Article

An acidified solution of 0.05 MZn²⁺ is saturated with 0.1 M H₂S. What is the minimum molar concentration (M) of H⁺ required to prevent the precipitation of ZnS?

Use sp(ZnS) = 1.25 x 10-22 and overall dissociation constant of H2S, KNET = 1 2 = 1 × 10-21. Answer: 0.2... View Article

Tin is obtained from cassiterite by reduction with coke. Use the data given below to determine the minimum temperature (in K) at which the reduction of cassiterite by coke would take place.

At 298 K: ∆ 0(SnO2( )) = −581.0 kJ mol−1, ∆ 0(CO2(g)) = −394.0 kJ mol−1, 0(SnO2(s)) = 56.0J K−1mol−1,... View Article

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