What is the partial pressure of oxygen collected over water if the temperature is 20.0°C and the total gas pressure is 735 mmHg?

1 Answer
Nov 22, 2015

#"718 mmHg"#


The trick here is to realize that the oxygen, which is collected over water, will be mixed with water vapor.

This means that the *total pressure8 of the mixture will have two components

The vapor pressure of water at that temperature is approximately #"14.47 mmHg"#


This means that you will have

#P_"total" = P_"oxygen" + P_"water"#

#P_"oxygen" = "735 mmHg" - "17.47 mmHg" = color(green)("718 mmHg")#