why can't we pour water into hot oil but can pour oil into boiling water?

Answer 1

Hot oil doesn't boil by itself. So when you add water to hot oil it basically super heats the water and causes an almost explosive force. Boiling water on the other hand is already turbulent, adding oil or anything else (except salt) wont really change anything.

Answer 2

It has to do with the physical and chemical properties they each have which would take a longer time to explain than you'd like, just never, ever get a glass of water, a drink, or any other liquid that is not cooking oil where it can spill into a fryer that has hot oil in it. If it does, it turns into steam instantly, and can violently spray/explode hot oil in all directions. Also, be careful even when you add food to a deep fat fryer. If the fat is too hot, or if there are pockets of liquid in the prepared food, the hot fat can spray about.

When hot oil is poured into boiling water the reverse is NOT true, the water, even though hot, acts as a heat sink and dissipator. Again, this is because of the physical and chemical characteristics of each substance and I have no idea how much chemistry and physics you've studied to explain it.

It's sort of like explaining that if you mix Clorox and ammonia while cleaning the bathroom, you could die from the poison gas.
Without some chemistry to understand the equations, you just have to take it on faith.

Answer 3

The oil can reach temperatures well above the boiling point of water. When you pour water into oil above the boiling point of the water, it converts to steam which expands rapidly amounting to almost an explosion. The result is a big splash of hot oil that could burn you badly.

Water, on the other hand, does not get hot enough to boil the oil so there is no danger of explosive expansion.

Answer 4

since water and oil don't mix the first is highly dangerous. the chemicals don't mix, but heat is transfered and if you do you just made your very own geyser from the superheated water.