Multiple Choice QuestionsThe number of grams/ weight of NH4Cl required to be added to 3 litres of 0.01 M NH3 to prepare the buffer of pH = 9.45 at temperature 298 K (Kb for NH3 is 1.85 × 10-5)
0.354 gm
4.55 gm
0.455 gm
3.55 gm
A 6% solution of sucrose C22H22O11 is isotonic with 3% solution of an unknown organic substance. The molecular weight of unknown organic substance will be
684
171
100
342
Commercially available H2SO4 is 98 g by H2SO4 and 2g by weight of water. It's density is 1.38 g cm-3. Calculate the molality (m) of H2SO4 (molar mass of H2SO4 is 98 g mol-1).
500 m
20 molal
50 m
200 m
In order to oxidise a mixture of one mole of each of FeC2O4, Fe2(C2O4)3, FeSO4 and Fe2(SO4)3 in acidic medium, the number of moles of KMnO4 required is:
1.5
3
2
1
The vapour pressures of pure liquids A and B are 400 and 600 mm Hg, respectively at 298 K. On mixing the two liquids, the sum of their initial volumes is equal to the volume of the final mixture. The mole fraction of liquid B is 0.5 in the mixture. The vapour pressure of the final solution, the mole fractions of components A and B in vapour phase, respectively are:
500 mm Hg, 0.4, 0.6
450 mm Hg, 0.4, 0.6
500 mm Hg, 0.5, 0.5
450 mm Hg, 0.5, 0.5
What would be the molality of 20% (mass / mass) aqueous solution of KI? (molar mass of KI = 166 g mol-1)
1.08
1.35
1.51
1.48
The strength of 11.2 volume solution of H2O2 is: [Given that molar mass of H=1 g mol–1 and O=16 g mol–1]
1.7%
34%
13.6%
3.4%
At 300k and 1 atmospheric pressure 10ml of a hydrocarbon required 55mL of O2 for complete combustion and 40mL of CO2 is formed. The formula of the hydrocarbon is:
C4H6
C4H7Cl
C4H8
C4H10
For a reaction, N2 (g) + 3H2 (g) → 2NH3 (g); Identify dihydrogen (H2) as a limiting reagent in the following reaction mixtures.
35 gm of N2 + 8 gm of H2
28 gm of N2 + 6 gm of H2
56 gm of N2 + 10 gm of H2
14 gm of N2 + 4 gm of H2
