# Chemistry

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Freezing point of pure water = -2, Freezing point of Unknown solution = -1
Mass of unknown in 50g of water = 1.9964g. Calculate the delta T for the solution of the unknown solid and determine the molecular weight of the unknown solid.

• Chemistry -

Freezing point is supposed to go down. It went up. Bad data. Means nothing to me.

• Chemistry -

If it had gone down then how would we calculate it

• Chemistry -

delta T = Kf*m
Substitute for delta T and Kf and solve for m = molality
In your case delta T is +1 and kg solvent is 0.050.

m = mols/kg solent
You have m and kg solvent; solve for mols.

mol = grams/molar mass. You have mol and grams, solve for molar mass.

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