• The mass of Mg metal (99.5% pure) to prepare a 1000 ppm Mg solution in a 500 mL volumetric flask.

Question

The mass of Mg metal (99.5 pure ) to prepare a 1000ppm Mg solution in a 500mL volumetric flask

Answer 1

1000 ppm = 1000 mg/L = 1 mg/mL = 500 mg / 500 mL

Hence you need 500 mg = Mg

Since your Mg metal is 99.5% pure, you need to weigh

500 mg / 0.995 = 503 mg