Talk:Parts per million
From Academic Kids
"The ppm value is equivalent to the absolute fractional amount multiplied by one million." This needs to be expanded. For those who actually need this article, this will be more confusing than the words "parts per million."
An example would help (I mean, an example like "a drop of blood in a 50 gallon drum would be about n parts per million"). --Larry Sanger
Is the exact calculation/definition:
ppm = solute / solvent * 1000000 ?
or
ppm = solute / total solution * 1000000 ?
or could be both ? like we use percentage, sometimes it needs to specify which two we are comparing ?
also, is it must be the same units ? like mass over mass,
or it could be mass over volume, without specifying other variables like temperature ?
