Eli5: Exploding water bottle


I put boiling water and dish soap into my bottle to get rid of a smell, i shook it up and when i opened it up it blew soap around 8 feet across my kitchen, what happened?

In: Chemistry

The foaming agent in the soap was activated by the heat and mechanical disturbance, releasing gas (likely by decomposing).

While the bottle was closed the gas didn’t have anywhere to go and so most of it dissolved into the water. Once you opened the bottle, the pressure dropped, and since hot water is really awful at holding (most) dissolved gasses those gasses instantly transitioned from an aqueous solution to a gas, expanding several thousand times in volume, and pushing away the (more or less) incompressible liquid around them.

Bonus info: this is why you need special non-foaming detergent for dishwashing machines.

Edit: depending on how full the bottle was it might have just been thermal expansion of the air in the “empty” part of it.

The water heated up the air in the bottle when you shook it, so the pressure went up. That got released when you opened the bottle, and it blew your soap around.