Im doing a lab and one of the questions says to "correct the barometric pressure for the vapor pressure of water?" What exactly is this question asking me to do? Like what should i be trying to find? ATM's?

Question

anonymous · Answer

To clarify, this is a lab to find the molar mass of butane usinf ideal gas laws and what not.  so we during the lab we find the barometric pressure of butane+water pressure and the pressure of water vapor bot in mmHg. But it says to correct butane for the vapor pressure

anonymous · Answer

and a later question says to correct liters of the gas into stp, but liters is STP so im confused as to what it means by "correct"

miracrown · Answer

Well, do you know what 'the barometric pressure' means?

miracrown · Answer

It's basically the atmospheric pressure, so I don't know if you noted the pressure on a barometer in the lab that day, or if you're just supposed to assume that it was 1 atmosphere.

Now how did you measure the volume of the butane, was it collected in a glass tube or something, which was sealed off from the atmosphere by water? @TheSeabass

miracrown · Answer

It's a convenient and safe way of collecting and measuring gases,
but besides the gas you're collecting, a small amount of water vapor forms in the vessel where you are collecting your gas. and you need to correct for that ...

So the amount of water vapor depends on the temperature, was there a particular temperature that you did the experiment at?

anonymous · Answer

yes i have the barometric pressure and water vapor pressure. I found the volume by subtracting the volume of water before displacement by the volume of water in the flask after some is displaced by the gas