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3 years ago

Calculate the molecular mass of the nonionic solutes.

Chemistry

1 answer:

3241004551 [841]3 years ago

8 0

Answer:

The molecular mass of the nonionic solutes is 124,90 g/m

Explanation:

This is the formula for boiling point elevation.

ΔT = Kb . m

Where ΔT = Tb (solution) - Tb (pure solvent)

Where Kb = the ebullioscopic constant

Where m = molality (moles of solute in 1kg of solvent)

Kb for water is 0,512°C/molal

100,680°C - 100°C = 0,512°C/molal . m

0,680°C = 0,512°C/molal . m

0,680°C /0,512 molal/°C = m

1,32 molality (This are my solute moles in 1kg (1000g) of solvent but I have just 390 g, so let's build the rule of three)

1000 g _____ 1,32 moles

390 g ______ (3,90 g . 1,32 moles) / 1000 g = 0,5148 moles

Molecular mass = g/ mol (mass/moles)

64,3 g /0,5148 moles = 124,90 g/m

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