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 750 mL of a solution that has a concentration of Na^+ ions of 1.3 M?

Question

Express your answer numerically in grams.

Answer 1

M = moles/L
1.3 M = moles/0.750
Solve for moles.
Then moles = grams/molar mass.
Solve for grams. That will give you g Na3PO4 to make 1.3 M Na3PO4 so divide that number by 3 to give 1.3 M sodium ions and not Na3PO4.

Answer 2

111.797

Answer 3

159.85