How many grams (to the nearest 0.1 g) of Fe(NO3)39H2O are required to prepare 250.0 mL of a 0.450 M solution of Fe(NO3)39H2O?. How many grams (to the nearest 0.1 g) of Fe(NO3)3ú9H2O are required to prepare 250.0 mL of a 0.450 M solution of Fe(NO3)3ú9H2O?