Posted by Jana on .
0.015 moles of a compound are dissolved in 18 fl. oz. of water. At what temperature will the solution begin to freeze? The density of water is 1.00g/mL

AP Chemistry 
DrBob222,
Convert 18 fl oz to grams and to kg. 1 oz = 28.35 grams.
molality = mols/kg solvent
Solve for molality.
Then delta T = Kf*m
You know Kf and m, solve for delta T, then subtract from zero C to find the new freezing point. 
AP Chemistry 
kabiru,
what will be mass of 0.015 moles of sodium hydroxide sulphet where the molar mass of sodium hydroxide 120g/moles.