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How much would the freezing point of water decrease if 4 mol of sugar were added to 1 kg of water(k=1.86 c/mol/kg for water and i=1 for sugar

Calculate the mass of 0.750 mol of the following substance. na3po4. , i'm not quite sure on how to set up the problem to solve! : (

Nh4no3 n2o + 2h2o a chemist who is performing this reaction starts with 160.1 g of nh4no3. the molar mass of nh4no3 is 80.03 g/mol; the molar mass of water (h2o) is 18.01 g/mol. what mass, in grams, of h2o is produced?