Sodium phosphate has the formula Na3PO4. Determine the concentration of sodium ions in a 0.6mol dm-3 solution of sodium phosphate?

Lets see, dm-3 means decimeters cubed. 1 cc = 1 mL. There are 1000 mL in a L. There are 1000 cc's in a dm-3. So I'm guessing dm-3 is a fancy lingo for liter. There are 3 moles of sodium ions per sodium phosphate mole. That means there will be 3 times the Ions as the number of molecules. That means there will be (3 x 0.6) 1.8 moles of sodium ions in 1L of 0.6 molar sodium phosphate solution.