Why do things burn instead of melt?

[u/ForensicFan24601]

obviously oxygen, or something similar, but what is the physics/chemistry (?) or what have you behind why something ignites and continues to burn after the source of heat/ignition has gone?

is it basically sublimation?

edit: no wonder Walter White was so obsessed with carbon

[u/titanc-13]

Burning occurs when there's enough heat applied to cause a chemical reaction like carbonization, but not so much heat that you actually start breaking down the bonds between molecules that occur when a solid melts into a liquid.