What weight of lead nitrate in grams would need to be dissolved in 400 mL of water to prepare a 270 ppm solution of Pb2+?

Answer 1

1 ppm = 1 mg/L
270 ppm = 270 mg/L
Convert that to mg/400 mL.
270 x (400/1000) = ? mg in 400 mL
Change to grams.

Answer 2

0.108