H3PO4 has molecular weight of approximately 98 grams per
mole. 4.50 M is equal to 4.50 mole per 1000 mL solution of H3PO4. 255 mL times
4.50 mol /1000 mL times 98 g/mol is equal to 112.455 grams. Note that I
automatically equate 1 Liter to 1000 mL since the given volume is in mL for
easier computation.
