Some metals like iron and tungsten glow when heated to extreme temperatures, and even when they reach a melted state. Yet some other metals such as aluminum do not glow at all even when heated beyond their melting point.
Is it just some specific properties of certain metals, or is it some of the elements within metals that can cause it to glow when heated?
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I think it has to do with the melting points. Some metals will melt much faster before they even glow, e.g. gold, which has a low boiling point. Others will glow before they reach the melting points.
Impurities may also affect the way metals behave regarding heating.
P.s. my chemistry is below useless, but I think what I said makes sense 😁😄😄
All metals will glow when heated. In fact **everything** glows at whatever temperature they are, and more interestingly everything glows the **same color** when heated to a specific temperature! This is how the “laser thermometers” work, they are just infrared sensors that detect the wavelength of infrared light emitted by objects and from that deduce what temperature they must be.
Most objects we encounter on a daily basis are glowing in a wavelength we can’t see with our eyes, some frequency of infrared. As objects become hotter though the frequency of light they emit increases (it is actually a range, but the peak frequency of emission increases). At around 525 degrees Celsius the emitted light begins to enter the visible range and we will begin to perceive a glow. In fact if you look on the back of a light bulb box you will see a little chart called “Color Temperature” with a sort of orange color on one end at 1000K and the other end being a blue color at 10,000K. That “K” is “Kelvin”, as in the temperature measurement. An object at 1000 Kelvin would glow that orange color, in this case that object being the incandescent filament of a light bulb.
Aluminum definitely does glow when heated to its melting point. However aluminum is also very conductive to heat so it can be prone to developing a sort of “skin” of cooler metal on its surface which would be below the temperature to visibly glow. If all the aluminum is molten though it does glow.
Well in cases like aluminum it just melts before it gets hot enough to glow good and proper. You can keep heating the molten metal and it glows like you expect for the temperature though.
https://i.stack.imgur.com/uGB7l.jpg
At lower temps the color of the metal itself can show through since the blackbody glow isn’t as intense in the visible range. But you get up to like 2000F anything that isn’t vapor yet is pretty much the same color.
All materials will glow the same color at the same temperature. Glowing purely a function of the temperature, rather than the material. Even gas or liquids will glow. The only thing the material effects is how bright the glow is. Naturally dark materials like iron, tungsten, or carbon will glow more brightly than white or silvery materials.
Because different metals have different melting points, some metals will glow as solids, while others will melt into a liquid well before they reach the temperature where they will glow (mercury, lead, etc). If you continue to heat the liquid metal to the same temperature as the glowing iron, the liquid will glow the same color as the iron.
Metals tend to have high melting points and the ones we usually deal with don’t burn in the Earth’s atmosphere. Many non-metal materials (wood, plastic) will burn before they get hot enough to melt or glow with heat, so we don’t think of them as something that can glow. Non-metals with high heat resistance will glow at high temperature, the same as metals will.
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