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When one heats oil in a pan, there comes a time when it starts boiling (bubbles coming up) just like water.
Now I know that water bubbles are formed to the the increase in the K.E of molecules and thus the breakage intermolecular forces. Does the same happen with oils?
Oil does boil like water, at least in theory, but in practice you should never see oil boil during cooking. The temperatures cooking oils will boil at is much higher than their smoke points. You never want to heat oil to (or above) its smoke point as - aside from generating smoke - it also has a big negative effect on the flavour of the oil and will spoil whatever you're trying to cook.
Even worse, as you heat oil beyond its smoke point you run the risk of reaching its flash point, where the oil can catch fire. A fire which can easily get out of control and result in a disaster. So if you see oil smoking in your pan you want to immediately turn down the heat, not just so you don't ruin your meal, so you don't risk ruining your kitchen.
Finally the bubbling you see when frying things in oil isn't the oil boiling. It's water vapour from whatever you're cooking. Since when frying the temperature of the oil is significantly higher than the boiling point of water, any water the hot oil comes into contact will turn into vapour.
Refineries boil billions of gallons of oil every day. They do it in an oxygen free, enclosed environment at various pressures. Depending on the unit , they may boil a little water in there too. Cooking oils can also be boiled away;although temperatures will be so high that it should be done in an oxygen free, enclosed environment.
I would say no. There is some room for interpretation, but even if you count it as "boiling", then it is not the same way as water does.
First, oil is not a pure chemical compound, it is a mixture of fatty acids and other stuff extracted from the plant. Even you could define one exact mixture as "oil" and it were "boilable", you still probably wouldn't have a strictly defined boiling point. "Probably", because some mixtures do have a boiling point (as opposed to a temperature range in which they boil) - I am not enough of a chemist to know which have a point and which a range.
Second, oil is not even a well defined mixture. It varies from bottle to bottle. So some oils would have a different behavior during "boiling" than others.
Third, when water boils, you can condense it and it becomes water again. It just undergoes a phase change at its boiling point, no further changes. But for oil, this is not true. While still in liquid state, heating causes it to undergo pyrolysis and other changes - you see it smoking when you heat the pan, it polymerizes if thin enough (that's how you season iron pans), etc. So whatever mixture it was before heating, it is not the same mixture when it reaches its boiling temperature range, it has changed chemically. So if you can heat it to a temperature at which it does turn from liquid to gas (and it doesn't completely burn away, or polymerize into a lump, etc.), then condense it, whatever you condensed won't be the same thing you started out with. It is much more than just a phase change.
I guess people can still make the case that there is some temperature range at which whatever you have in your vessel (which is no longer the oil you started out with) could turn from a liquid to a gas, and this should be described as "the oil is boiling". So I am not saying a firm, emphatic no. But as you see, even if you find the use of the label "boiling" acceptable, it is actually very different from what most people think of when they think of boiling, or from how water boils.
Like mentioned above, oil has a decomposition point that is lower than its boiling point. So when you heat it, it will decompose before turning into a gas. The gas you do see is smoke from the oils combusting / pyrolyzing. However, if you were to heat oil in an oxygen free environment (O2 is required for combustion) then you might be able to form gaseous. This will depend on how hot you have to heat it - if the heat required to form the gas is larger than the energy of the atomic bonds in the molecule, then the molecule will decompose (pyrolyze) before becoming a gas.
The smoke coming off is the oils version of "steam" But only a part of it comes off the molecule, some of stays behind in the slimy muck permanently.
I think when your having a cigarette, some of the smoke your inhaling is this same smoke from the tobacco leaf, but I'm not sure.
