Does the Ratio of Propane to Butane Change in a Half-Empty LPG Cylinder?

[Saint1968]

If I have a LPG-cylinder that contains a mix of 50 % Propane and 50 % Butane, and I use half of the content.
Will the mix still be 50/50 between Propane/Butane? Or will one of the gasses be used faster than the other?

 

[Bystander]

"Yes."

You will have to be more specific about conditions.

 

[Chestermiller]

The Propane has a higher vapor pressure than the Butane, so the propane will be used faster, and the liquid will become richer in butane.

 

[Averagesupernova]

It depends on whether you are just using vapor off the top of the tank or taking liquid.

 

[Saint1968]

"Yes."

You will have to be more specific about conditions.

The outtake of gas will be in gas-phase (Vapor)

 

[Saint1968]

It depends on whether you are just using vapor off the top of the tank or taking liquid.

The outtake of gas will be in gas-phase (Vapor)

 

[Saint1968]

The Propane has a higher vapor pressure than the Butane, so the propane will be used faster, and the liquid will become richer in butane.

So, the gasses keep their own properties and will not be a combination of the two?

 

[Chestermiller]

So, the gasses keep their own properties and will not be a combination of the two?

The exit vapor will be an intimate mixture of butane and propane in proportions described approximately by Raolt's Law.