a solution is 0.0300 m in Sodium. How many grams of sodium carbonate are necessary to prepare 900.0 ml of this solution?
I don't know where to start on this.
I assume you meant Molarity instead of m molality.
Na2CO3 (aq). If the solution is .03M n Na, it is .015M in sodium carbonate.
masssodumcaronate=.015*molmasssodiumcarb*.900