If sodium sulphate is considered to be completely dissociated into cations and anions in aqueous solution, the change in freezing point of water (ΔTf), when 0.01 mol of sodium sulphate is dissolved in 1 kg of water is (Kf = 1.86 K kg mol–1)
6.02 × 1020 molecules of urea are present in 100 mL of its solution. The concentration of urea solution is (Avogadro constant, NA = 6.02 × 1023 mol–1) |
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1.00 g of non–electrolyte solute (molar mass 250 g mol–1) was dissolved in 51.2 g of benzene. If the freezing point depression constant, Kf of benzene is 5.12 K kg mol–1, the freezing point of benzene will be lowered by |
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An aqueous solution is 1.00 molal in KI. Which change will cause the vapour pressure of the solution to increase? |
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The molarity of a NaOH solution by dissolving 4 g of it in 250 ml water is |
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What is the osmotic pressure of a 0.0020 mol dm–3 sucrose (C12H22O11) solution at 20°C? (Molar gas constant, R = 8.314 JK–1 mol–1, 1 dm3 = 0.001 m3? |
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The Henry's law constant for the solubility of N2 gas in water at 298 K is 1.0 × 105 atm. The mole fraction of N2 in air is 0.8. The number of moles of N2 from air dissolved in 10 moles of water at 298 K and 5 atm pressure is |
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0.5 molal aqueous solution of a weak acid (HX) is 20% ionized. If Kf for water is 1.86 K kg mol–1, the lowering in freezing point of the solution is |
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pA and pB are the vapour pressure of pure liquid components, A and B, respectively of an ideal binary solution. If xA represents the mole fraction of component A, the total pressure of the solution will be |
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Benzene and toluene form nearly ideal solutions. At 20°C, the vapour pressure of benzene is 75 torr and that of toluene is 22 torr. The partial vapour pressure of benzene at 20°C for a solution containing 78 g of benzene and 46 g of toluene in torr is |
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6.02 × 1020 molecules of urea are present in 100 mL of its solution. The concentration ofsolution is |
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