Question

Is burning a physical or chemical property?

Answer 1

It is physical as you're not changing the chemical properties you're just changing the state

Answer 2

Burning is a chemical process by which a fuel is oxidised.

Take for example the burning of methane (CH4):
CH4 + 2O2 --> CO2 + 2H2O

As you can see the methane reacts with the oxygen to produce carbon dioxide and water, releasing heat in the process. The technical name is combustion.