May I get help on this?

Question

Express each of these concentrations in parts per million (ppm).

6.3 milligrams per kilogram of water

Concentration=ppm?

6.3 micrograms per kilogram of water

Concentration=ppm?

6.3 nanograms per kilogram of water

Concentration=ppm?

Answer 1

There are 1000 g in 1 kg and there are 1000 mg in 1 g.

It means that there are

1000 x 1000 = 1,000,000 = one million mg in 1 kg

So the handy formula to memorize is 1 ppm = 1 mg/kg

Can you answer the questions now?

Hint: 1 mg = 1,000 mcg = 1,000,000 ng