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But the nuclei in metal are more like the grapes in a Jell-O fruit cocktail. They're all linked together by a goop of electrons the Jell-O , it's tough to get just one grape out without pushing a bunch of the jello around and making a big mess, and if you shake the jello, all the grapes bounce in the same way.
So when you heat up a metal, the goop of electrons physicists call it the 'sea' of electrons can start getting hot and moving really fast, but all the nuclei stay in the same place and just pass the electrons back and forth amongst themselves.
So a metal can get really, really hot before it gets so hot that the nuclei stop sticking together. That's why you can put your aluminum foil in the oven and it will get hot, but you won't be able to turn up the heat enough to melt it. Why does aluminum foil not get hot when it is in a hot oven? Answer 1: Actually, it does get hot. Answer 3: Actually, aluminum foil does get hot when it is in the oven.
Answer 4: Since aluminum foil has a lot of surface area and is very thin and heat travels within aluminum very well, it is going to cool off very quickly in air when you remove it from the oven. Here is a question for you: Let's say that you are about to jump into a swimming pool. Answer 5: Hmmmm. Aluminum has a very low specific heat capacity and foil is very thin, these combine together to get it a very low thermal mass it cannot hold a lot of heat.
It also has a very high surface area to volume ratio and a very high thermal conductivity. This means that the heat that it can store can move in and out of it very very fast. When you combine these, Aluminum foil can go from red hot to room temperature in a matter of seconds. The very low thermal mass means that with very thin foil it might be degrees, but putting that heat into your finger only raises your finger by 20 degrees, and results in no burn.
Not only does aluminum change temperature rapidly and lose heat to the air before you can touch it, but a sheet of aluminum foil has very little mass. This means that the total amount of stored heat in the area you touch is very low. Heat capacity is related to density mass per unit volume , heat transfer moving heat out of an object is related to surface area. The aluminum heats up to the same temperature as everything else in the oven quite a but faster than anything else in the oven — aluminum is a good thermal conductor , but a sheet of foil has almost no mass, but tons and tons of surface area.
The biological side is being neglected, though. Try taking the foil out of the oven then quickly crush it into a tight ball. The greater amount of mass, the longer it takes to heat or cool. Very little mass is used in various foils, whereas your cookie sheet is several hundred times thicker, thereby providing a greater mass which retains the heat longer.
That was a great symposium on Microwaves Neema. And love the Tin man I wonder, was Rin Tin Tin a metal dog? Tin foil or more properly, aluminium foil is an awesome conductor. That means that it transfers the heat in your oven through to whatever it touches. However, once it is removed from a heat source, that very conductivity means it cools down superfast, and when you bring it out of the oven it almost immediately returns to the ambient room temperature.
The foil does get hot, as hot as the rest of the oven. But the material is so thin, that it cannot retain heat for very long. If you were to use a much heavier duty foil you might feel the heat a bit longer. It does get hot.
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