[poochiram]

How to convert 37 ppm Mg into moles?

[Mitch]

Show that you have attempt the problem before posting.

[AWK]

ppm is a concentration unit. It cannot be converted to amount of matter (moles) directly.
You can calculate moles of substance in solution (or mixture) of known volume or mass.

[kevins]

poochiram:

ppm = part per million

I guess you have a aqueous solution contains 37 ppm Mg

37 ppm Mg solution = 37 milligram of Mg in 1 L water.

[AWK]

http://en.wikipedia.org/wiki/Parts_per_million

[Donaldson Tan]

ppm is a mass fraction. it is similar to percentage where u multiply the fraction by 100%. In ppm case, u multiply by 1 million.

ppm of a solute = (mass of solute) / (mass of solvent) x 10⁶

37ppm of Mg tells u every million kg of solvent corresponds to 37kg of Mg. Given this information, you should above to work out its molar concentration by converting the required mass to moles.