Hi...Prbably a stupid question but here it goes:(adsbygoogle = window.adsbygoogle || []).push({});

I have some equations here, some of them have a G for rate of generation and others have E for rate of evaporation (both of them have units of volume per time).

My question is: if I know that I have 3 galons of a chemical at the beggining of the day in one tank and at the end of the day I only have 2 galon...then I lost 1 galon per day...but is this number E or G? I mean...I don't understand what is the difference, I know there is an equation relating them but I don't understand the concept.

**Physics Forums | Science Articles, Homework Help, Discussion**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Ventilation Systems

**Physics Forums | Science Articles, Homework Help, Discussion**