Fire and liquid Oxygen.

[flatmaster]

Earlier, I had posted that I thought that I had made liquid oxygen. People seemed skeptical that it would work, but I did an experiment to prove the concept.

On a ring stand, I had some burning paper towel. I put some liquid nitrogen in a pie tin and allowed atmosphere to condense on the outside. Allowing this cold liquid to fall on the burning paper produced small spurts of burning paper. It was a bit difficult to keep the cold nitrogen vapors from blowing out the fire, but if the pie tin was held high enough, this was not an issue.

I know this isn't any ground-breaking science, but it sure was fun! Should I write a paper?

 

[Q_Goest]

Hi flatmaster. What you saw was slightly concentrated oxygen. Oxygen condenses preferentially on the liquid nitrogen pan you had, producing an oxygen rich liquid because oxygen condenses at a slightly higher temperature.

 

[flatmaster]

That's what I figured. It seems quite amazing that the cold nitrogen that's in there doesn't blow out the flame when it expands. I suppose the next step is to collect some and measure the relative concentrations. How can I do that?

 

[Q_Goest]

Measuring oxygen concentration is much easier & less expensive than measuring nitrogen. See what's available to measure O2 concentration. Perhaps you could collect the drops off the pan by sucking them into an evacuated container.