Posted by Fai on .
8.058g x 10-2 kg of washing soda na2co3 10h20 is dissolved in water to obtain 1L of a solution of density 1077.2kg/m3. Calculate the molarity, molality and mole fraction of na2c03 in the solution?
mols Na2CO3.10H2O = grams/molar mass.
Then M = mols/L soln.
m = mols/kg solvent.
Use density to convert L soln to grams soln and subtract g Na2CO3.10H2O to find g solvent. Convert g solvent to kg and apply the definition for m.
mols fraction. You have mols solute. Convert grams solvent to mols. Add mols solute + mols solvent to obtain total mols. Then mole fraction Na2CO3.10H2O = mols Na2CO3.10H2O/total mols.