At what temperature can ethanol be considered dangerous?

Question

Hi everybody, I'm doing a science experiment where I'm pouring 100% pure ethanol into a bottle, placing that plastic bottle into a pot,and placing the pot onto a stove, and raising the temperature to 30-40 degrees C. I'm not sure if this is safe, b/c the bottle says that pure ethanol should not even be exposed to sunlight for long amounts of time.
please consider your response carefully because this is a potentially dangerous experiment, and I am taking all responses seriously.

I'm trying to demonstrate the temperature dependence of viscosity on a pure liquid such as ethanol.

Answer 1

The temperature ethanol is dangerous depends on the reaction conditions, what is the scale of the reaction...
Since this sounds like an experiment done at home (a chemist would never heat an organic solvent in a plastic bottle) the temperature it should be considered dangerous is 16.6 deg C (or 62 deg F).

Ethanol is is highly flammable. It has a flash point of 16.6 deg. C, which means that at this temperature vapours of ethanol can catch on fire.

With the proper glassware it can be handled safely at a much higher temperature. If you have to ask this, then you should be using it.

Answer 2

I have never considered ethanol particularly dangerous except that it is more flammable at higher temperatures. There may be a possibility that it might form an diethyl ether. If you let it evaporated the ethyl ether could form Diethyl ether peroxide which could spontaneously ignite. Diisopropyl ether peroxide is very dangerous but I have never really heard of a significant hazard from ethanol.

Answer 3

At standard pressure, ethanol boils at 78.4 °C.

Unless you have very tight control of your heat source, this experiment might be dangerous, since vaporized ethanol is highly flammable and somewhat toxic.

What are you trying to demostrate?