In an experiment, 16.8 g of k2so4 was dissolved in 1.00 kg of water to make a solution. the freezing point of the solution was m

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In an experiment, 16.8 g of k2so4 was dissolved in 1.00 kg of water to make a solution. the freezing point of the solution was m

easured to be −0.405°c . calculate the van't hoff factor (i) for this solution. the freezing point of pure water is 0°c (exactly) at 1 atm pressure and the molal freezing-point depression constant for water is 1.86°c/m.

Chemistry

1 answer:

Mashutka [201] · Answer 1 · 2022-06-11T14:53:40+03:00

Answer is: V<span>an't Hoff factor (i) for this solution is 2,26.
</span>Change in freezing point from pure solvent to solution: ΔT =i · Kf · m.
<span>Kf - molal freezing-point depression constant for water is 1,86°C/m.
</span>m - molality, moles of solute per kilogram of solvent.
n(K₂SO₄) = 16,8 g ÷ 174,25 g/mol
n(K₂SO₄) = 0,096 mol.
m(K₂SO₄) = 0,096 mol/kg.
ΔT = 0,405°C.
i = 0,405 ÷ (1,86 · 0,096)
i = 2,26.