Hello.
I bought the book "Quimica" (Chemistry in english). I started to read it and a notice this. In page 3 it says that in STP water in gas state has Xxxx density. How do you can have water in gas state at STP? That is what I dont understand.
Thanks!
Dear Emilio,
"STP" means "Standard Temperature and Pressure" which is defined as 0'C, 1atm. So, as long as water can exist in a vapor state at those conditions (it can - see the previous response from Alex) we can calculate (or measure) the amount water in a given volume in order to calculate a density.
Best regards,
Steven
The vapor pressure of water at 0°C is 4.6 torr:
Vapor Pressure of Water from 0 °C to 100 °C
You could put 4.6 torr into the Ideal Gas Law
PV=nRT
with R = 62.36 L torr/mol K, T = 273.15K and n = 1 and solve for the molar volume. Then, calculate density (18.02 grams/volume).