Passage IIIA solution containing 0.684 g of cane sugar (C12H22011) in ...
From ΔT, of cane sugar, K, can be determined.
For NaCI solution,
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Passage IIIA solution containing 0.684 g of cane sugar (C12H22011) in ...
Explanation:
The van't Hoff factor (i) is a measure of the number of particles that a solute molecule dissociates into when it is dissolved in a solvent. It is used to calculate the freezing point depression or boiling point elevation of a solution.
To calculate the van't Hoff factor (i), we need to compare the experimental freezing point depression of the solution with the expected freezing point depression based on the concentration of the solute.
Calculating the expected freezing point depression:
The expected freezing point depression (ΔTf) can be calculated using the formula:
ΔTf = Kf * m
Where:
ΔTf = Freezing point depression
Kf = Cryoscopic constant (freezing point depression constant) of the solvent (water in this case)
m = molality of the solute in the solution
The molality (m) can be calculated using the formula:
m = moles of solute / mass of solvent (in kg)
For cane sugar (C12H22O11):
Molar mass of cane sugar (C12H22O11) = 342.3 g/mol
moles of cane sugar (C12H22O11) = mass of cane sugar (C12H22O11) / molar mass of cane sugar (C12H22O11)
For NaCl:
Molar mass of NaCl = 58.44 g/mol
moles of NaCl = mass of NaCl / molar mass of NaCl
Calculating the experimental freezing point depression:
The experimental freezing point depression (ΔTf) is given in the problem:
For cane sugar solution: ΔTf = -0.037°C
For NaCl solution: ΔTf = -0.342°C
Calculating the van't Hoff factor (i):
The van't Hoff factor (i) can be calculated using the formula:
i = ΔTf (experimental) / ΔTf (expected)
For cane sugar solution:
ΔTf (expected) = Kf * m (cane sugar)
i (cane sugar) = ΔTf (experimental) / ΔTf (expected)
For NaCl solution:
ΔTf (expected) = Kf * m (NaCl)
i (NaCl) = ΔTf (experimental) / ΔTf (expected)
Calculating the van't Hoff factor (i) for cane sugar solution:
First, calculate the moles of cane sugar:
mass of cane sugar = 0.684 g
moles of cane sugar = 0.684 g / 342.3 g/mol
Next, calculate the molality of the solution:
mass of water = 100 g
mass of water = 100 g / 1000 g/kg
m (cane sugar) = moles of cane sugar / mass of water
Now, calculate the expected freezing point depression:
ΔTf (expected) = Kf * m (cane sugar)
Finally, calculate the van't Hoff factor:
i (cane sugar) = ΔTf (experimental) / ΔTf (expected)
Calculating the van't Hoff factor (i) for NaCl solution:
First, calculate the moles of NaCl:
mass of NaCl =