How many part per million in 1 microgram?

Answer 1

This question doesn't make sense. This is because the term parts per million means either weight per weight i.e. micrograms per gram or milligrams per kilograms, or weight per volume, i.e. milligrams per litre or micrograms per millilitre.

Answer 2

There is 1 ppm in 1 microgram/milliliter.

1 ppm = (liquid) 1 milligram/liter = 1 microgram/milliliter.

1 ppm = (solid) 1 milligram/kilogram = 1 microgram/gram