Molecular mass of NaOH = 23.0+16.0+1.00 = 40.0
Molecular mass of Na2O = 2*23.0 = 46.0
Equation of reaction:
Na2O + H2O = 2NaOH
So 1 mole of Na2O will produce 2 moles of NaOH, or
46 grams of Na2O will produce 2*40=80 grams of NaOH.
1.20*10^2 grams = 120 grams
Therefore
120 grams of Na2O will produce
120*80/46 = 208.7 grams of NaOH.
Answer: 209 grams of NaOH will be produced (to 3 significant figures)
