"The molecular weight of sodium chloride is 58.5 g/mol. How many grams of NaCl do you need to dissolve in 1.00 L of water to make a solution that is 500 ppm Na+?
Would you simply do:
500ppm = mg/1.0 L = 500 mg Na+
NaCl freely dissociates to Na+ and Cl- in a 1:1 ratio so would it also be 500 mg NaCl (0.5 grams)?