How many grams of table salt would have to dissolved in 125.0 g of water?

Question

to lower the freezing point by 1.90 degrees celsius?


kf = 1.86 K-kg/mol for water

Answer 1

The formula is delta T = Kf m (where m = molality)

You have the delta T and the Kf. Solve for the molality.

Molality is moles of solute in Kg. of solvent. You have 125 g. of solvent, so solve for the moles of NaCl. Now convert the moles to grams and you are done.