Pretty much the title. Chemically speaking what’s going on when this happens?
In: Chemistry
Boiling oil is hotter than boiling water.
So when you add cold water in boiling oil, it “explodes “ in water vapour, making the boiling oil jump out of the pan, it reaches the hot element under the pan and catches fire.
Water is heavier than oil, so it sinks. The boiling point of oil is also higher than that of water, so the water will also start boiling very rapidly. This produces a small explosion.
Only the oil on the surface actually burn. The steam explosion scatteres the oil into small droplets, with much higher surface area, making the oil effectively much more flamable. If the oil was already burning or there is something to set it alight, you get the fireball.
The boiling point of oil is also close to the ignition temperature, so boiling oil is very close to burning already. The oil can even spontaneouslu start burning.
All this makes grease fire tricky, as thay can start themselves and if you try to put it out with water, it will littereally blow up in your face.
The way to deal with grease fires is to deny them the oxygen they need to burn. This can be done by covering the fire with a lid. I always keep a lid ready when dealing with boiling oil.
It’s not a chemical reaction. The cold water rapidly boils into steam. The steam pushes a bunch of oil out of the pot and onto the burner, which ignites the oil.
Oil and water don’t mix, and oil floats in water. When you throw water in burning oil, the water doesn’t stick to the oil to smother the flames. Instead it displaces the oil and flash vaporizes, which splatters the burning oil everywhere without smothering the fire.
Water boils at 100 degrees C. Heated oil can get WAY hotter before either catching fire or evaporating…
If you add water… well, water and oil don’t mix. Furthermore the water just gets hot rapidly… so fast it basically hits boiling temperature almost immediately. Also since hot things expand, and boiling water is turning into a gas, it REALLY expands. This is happening as the water is getting under the oil since it’s been poured in and water is denser… so the water under the oil is expanding and throws the oil around. Oil, which I will remind you, is on fire or borderline so.
Flying oil is going to have more surface area exposed to air, and that means more opportunity to be in contact with oxygen which means MORE FIRE. Boiling oil is probably already on fire, or on the cusp of it. Being sprayed into the air helps the fire.
So by adding water to an oil fire, you’ve actually made the fire explode upwards and get bigger.
The water doesn’t set the oil on fire.
What the water does is flash boil into steam, carrying a fine mist of oil with it.
If there’s any open flame, this fine mist of oil catches fire almost as well as a gas, so it also burns rather spectacularly.
It does not set the oil on fire. There can be a huge fireball if you do that if the oil is already on fire or if there is a separate ignition source, a fire that is used to heat up the oil will be an ignition source
What happens is water is denser then oil so it sinks below the oil. The boiling temperature of the oil is higher then water and as a result the water will quickly be heated and start boiling.
When water turns from a liquid to a gas the volume increases by a factor of around 1000. The steam that is produced has to go somewhere and the way is up through the oil. It will push the oil up in the air in quite small droplets. Small droplets or solids of something that can burn in air give it contact with a loss of oxygen and all if it can burn very quickly if there is an ignition source.
Take a small glass of water put a straw in it and blow through the straw, that will result the air pushing water into the air like the boiling water does with the oil.
If you have oil that is hot enough but there is no ignition source present dropping the water in the oil will just create a steam explosion and throw the oil up in the air but there will not be any fire
If it is cold or warm water does not matter. With warm water it require less energy to get to boil so that will happen a bit faster. Because the process is so fast even with cold water you will not notice the difference.
Water goes into hot oil->Oil has a boiling temperature of 200 degrees celsius, so it’s way hotter than water->Water drops become steam almost (but not quite) instantly->Steam takes up way more room than liquid water->This expansion sends oil flying into the air.
At this point you either have “very hot oil flying all over the place” (which is bad and will probably burn someone) OR (if the oil is hot enough or if there are exposed sources of flame) “Drops of hot oil flying. And being surrounded by a lot of oxygen it reaches the perfect mixture of Hot+Fuel+Oxygen and ignites”
P.S: Here is a blast of the past, the [William Shatner+Melodysheep – Eat, Fry Love](https://youtu.be/Z4Qxqmhqj1A?si=cz71qOEOSV1hq_HV)
It’s not a chemical thing, just physical.
When oil is on fire, it’s extreme hot, about 230C (450F). So when you put water in oil, it vaporize immediately, causing mini-explosion, which splatter the oil everywhere, and that oil is on fire. To make matter worse, water is heavier than oil, which mean that whatever water that isn’t vaporize immediately is gonna go down at the bottom and then vaporize and explode, just to make sure that the oil splatter even harder.
Just to put it out there. Everyone should know not to put water in burning oil.
This german video shows great what happens if you do.
You definitely dont want to be in the same house.
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