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After you preform your experiment, you determine that the kf value for naphthalene is 6.91 °c/m . you are using 10g of naphthalene and added 1.0 g of your unknown. the the freezing point of the solvent decreased by 4.47 °c when the unknown was added. knowing this information, determine the molar mass of the unknown. g/mol

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Dejanras
Answer is: molar mass of compound is 154,58 g/mol.
m(naphthalene) = 10 g = 0,01 kg.
m(unknown compound) = 1,00 g.
ΔT (solution) = 4,47 °C.
Kf(naphthalene) = 6,91°C/m; cryoscopic constant.
M(unknown compound) = Kf(naphthalene)· m(unknown compound) ÷ m(naphthalene) · ΔT(solution).
M(xylene) = 6,91°C/m · 1 g ÷ 0,01 kg · 4,47°C.
M(xylene) = 154,58 g/mol.
mickymike92

Based on the Kf value and mass of the solvent naphthalene, the molar mass of the unknown compound is 154.58 g/mol.

What is the molar mass of a substance?

The molar mass of a substance is the mass of one mole of that substance.

The molar mass of a substance can be calculated from the Kf value and mass of the solvent naphthalene as follows:

mass of naphthalene = 10 g or 0.01 kg.

mass of unknown compound = 1.00 g

ΔT of the solution = 4,47 °C.

Kf value of naphthalene = 6.91°C/m;

  • Molar mass of unknown compound = Kf(naphthalene) × mass of unknown compound/ mass of naphthalene × ΔT

Molar mass of the unknown compound = 6.91°C/m · 1 g ÷ 0.01 kg × 4,47°C.

Molar mass of the unknown compound = 154.58 g/mol.

Therefore, the molar mass of the unknown compound is 154.58 g/mol.

Learn more about molar mass and Kf at: https://brainly.com/question/10674700