# How can I calculate the concentration of ethanol vapor in an airstream?

How can I calculate the concentration of ethanol vapor in an airstream?

The steady state generation flow rate (of the vapor) is 625 ft^3/min. The ambient temp is 50-60 F (we can use avg temp 55 F).

These vapors would come from liquid ethanol.

What more information do I need to calculate this concentration in kg/m^3 or ppm?

I apologize as I do not have a thorough chemistry background.

• Would you not need to know the rate of evaporation from the liquid ethanol? If the evaporation rate is very slow this will limit the amount of ethanol in the airstream, if high it may be the equilibrium vapour pressure. – porphyrin Aug 30 '17 at 13:08
• Are you saying that ethanol vapor is being generated at a rate of 625 $\ce{ft^3}$/min or that liquid ethanol is being generated at a rate of 625 $\ce{ft^3}$/min. – J. Ari Aug 30 '17 at 13:55
• @J.Ari Ethanol vapor. – VasNL Crafting Aug 30 '17 at 14:32
• @porphyrin ok, how shall I find the evaporation rate of the ethanol at this temp? – VasNL Crafting Aug 30 '17 at 14:33
• So if you know how much ethanol vapor you are generating you need to know what else is in the stream and measure the amount of the stream. Calculating a concentration at that point becomes trivial. – J. Ari Aug 31 '17 at 20:03