a)?The thermit reaction shows that aluminium is a reactive metal.?Aluminium is used for door-frames and window-frames.How can both these statements be true?b)?Aluminium conducts heat?Aluminium is used as a thermal insulator.How can both these statements be true?
Aluminum will combine with oxygen faster that any other element. Powdered aluminum is even used as a rocket fuel! That’s what is in the space shuttle’s booster rockets. When you have a piece of aluminum at home, say a sheet of foil, the surface has already oxidized. The surface of aluminum oxide protects the underlying metal from further oxidation so the foil remains inert, even in your oven. In foil thermal blankets, the extremely thin amount of aluminum foil reflects radiated heat. That’s its purpose there. It does however conduct latent heat very well. In your oven at home, you can pick up a hot food item by holding only the thin aluminum foil. This is because the foil is so thin that even if the temperature is, say 400 degrees, the tiny amount of foil that your finger touches does not have enough total heat to burn you.
for a) im not sure if door frames and window frames are made of pure aluminium. I dont think so. Surely its a compund of aluminium. b) Well..metals do conduct heat. Maybe your second point of aluminuium is a comparison of another metal.
