A scientist wants to make a solution of tribasic sodium phosphate,Na3PO4 , for a laboratory experiment. How many grams of Na3PO4 will be needed to produce 575mL of a solution that has a concentration of Na^+ ions of 1.40 M?

Answer: mass of Na3PO4 = _____

How is this question started/worked?

3 answers

Well, one gets three ions of sodium per molecule, so you want a Molarity of the salt of 1.40*3M

Molarity=moles solute/volume
= gramssolute/(molmass*volume)

solve for grams of solute you need use, then make up the volume desired with water.
Oppps. One wants TSP to be 1/3 the concnetration, not three times. ARRRGGGHHH.

Molarity= 1/3 * 1.40 M for the sodium triphosphate.
43.9