Question

What physical or chemical changes occur in a flame?

Answer 1

In a flame, you have a primary and secondary combustion zone, an interzonal region, and the tip of the inner cone. Just for kicks, the hottest part is near the top.

In a flame, you can obviously heat something up. That's a physical change (temperature ramping). However, there are occasionally elements that can oxidize in the flame, which is a chemical change (elementary state into oxidized state). Those form oxides or hydroxides, which (and you don't need to know this for a long time) act as spectral interferences in atomic absorption spectroscopy.

You can also melt and vaporize elements in flames, which are also physical changes (phase transitions).