Question

Why do some metal produce light when heated

Answer 1

Heating an atom excites its electrons and they jump to higher energy levels. When the electrons return to lower energy levels, they emit energy in the form of light. The colour of the light depends on the difference in energy between the two levels

Answer 2

In metals, when they are heated, the energy of the electrons increases. When the electrons return to lower energy levels, they emit energy in the form of light.