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the addition of 100 g of a compound to 750 g of ccl 4 lowered the freezing point of the solvent by 10.5 k. calculate the molar mass of the compound

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Final answer:

To calculate the molar mass of the compound, use the freezing point depression equation and the given data. The molar mass of the compound is 257.25 g/mol.

Step-by-step explanation:

To calculate the molar mass of the compound, we need to use the freezing point depression equation: ΔT = Kf × m.

In this case, the freezing point of the solvent was lowered by 10.5 K, and we know that Kf for carbon tetrachloride is 30.6 °C/m.

We can plug the values into the equation and solve for m:

m = ΔT / Kf

= 10.5 K / 30.6 °C/m

= 0.343 m.

Next, we can calculate the molality of the solution using the given data: molality = moles solute / mass solvent = X / 750 g, where X is the moles of the compound.

Since we already calculated the molality to be 0.343 m, we can solve for the moles of the compound:

X = molality × mass solvent

= 0.343 m × 750 g

= 257.25 g/mol.

The molar mass of the compound is 257.25 g/mol.

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