Calculate the molality of a solution prepared by dissolving 175 g of KNO3 in 750 g of water. (round to nearest hundreth)

We will get the molality from this formula:

Molality = no. of moles of solute / Kg of solvent

So first we need the no. of moles of KNO3 = the mass of KNO3 / molar mass of KNO3

no. of moles of KNO3 = 175 / 101.01 = 1.73 mol

By substitution in the molality formula:

∴ molality = 1.73 / (750/1000) = 2.3 Molal