Alkyl halides left in an open container what happens?

[saching]

Homework Statement

A student left some alkyl halides (RCI and RBr) in an open container for several hours. What happened to the composition of the halide mixture during that time? Assume that some liquid remains in the container.

Homework Equations

From: http://www.ipfw.edu/chem/254/254%20Fall%2005/CHM%20254%20Experiment%2024.htm The experiment had to do with measuring the nucleophilicity of different nucleophiles.

The Attempt at a Solution

I've thought about this problem a number of ways but can't seem to make much progress. At first I thought the halides might be volatile and evaporate into the vapor. That seems right given the hint--but that doesn't tell me what would happen to the composition of the halide mixture other than that the more volatile one would evaporate further.

I've also pondered the idea that water vapor from the air might go into the mixture and cause some kind of reaction although I think that would be a bit much to assume.

Any ideas?

 

[Borek]

At first I thought the halides might be volatile and evaporate into the vapor. That seems right given the hint--but that doesn't tell me what would happen to the composition of the halide mixture other than that the more volatile one would evaporate further.

If one evaporates more easily, mixture becomes richer in the other one. I don't think you can say anything more.