Chemical
The combustion of magnesium in air is a chemical reaction.
Propane pollutes the air around us. Propane is used as fuel and in chemical synthesis. Also propane is a nonrenewable gas.
chemical change occurs first. because first oxygen help in burning and form carbon-di-oxide which is a chemical change
Propane burning reacts with the oxygen in the air. C3H8 + 5O2 → 3CO2 + 4H2O
When a hot air balloon flies, the burner at the base of the balloon ignites propane to produce a chemical reaction that converts the propane into carbon dioxide and water vapor. This reaction releases heat, which warms the air inside the balloon, causing it to rise and lift the balloon.
Water.
Just plain old ordinary air, but heated by the flame of the burner (which I believe burns propane gas).
physical.
It is a physical change. I goes from white, to yellow, back to white.
The chemical that burns in air is oxygen. Oxygen is a highly reactive gas that readily supports combustion, which is why it is essential for most combustion processes to occur.
A propane air mixer in a gas appliance combines propane gas with air in the correct ratio to create a clean and efficient flame for heating or cooking. The mixer ensures that the gas burns efficiently and produces the desired level of heat without creating excess soot or carbon monoxide.
combustion