Calculate the amount of Na2HPO4*7H2O in grams needed to make 50 mL of a 0.40 M solution. I think this is dealing with molarity but i cant figure it all out for some reason? Help would be greatly appreciated.

Question

Calculate the amount of Na2HPO4*7H2O in grams needed to make 50 mL of a 0.40 M solution.  I think this is dealing with molarity but i cant figure it all out for some reason? Help would be greatly appreciated.

Bruce · Answer

just steps is all i really need i think i need the molecular weights first then just simple molarity am i correct?

Bruce · Answer

I got 0.02 g is this right?

DrBob222 · Answer

Use the Henderson-Hasselbalch equation.