A) In the fuel injector on top of the engine, changes occur as gasoline evaporates and mixes with air.
B) Inside the engine cylinders, the esplosion of the gasoline-air mixture produces hot exhaust gases, including water vapour, carbon dioxide, and nitrogen oxides.
C) The exhaust gases pass through the catalytic converter, where some harmful gases are changed into safer new gases.
D) The exhaust passes out the tailpipe. On a cold day, steam from the exhaust condenses into a white cloud.
E) As the steel of a car is exposed to air and water, a crumbly reddish-brown substance forms: the steel has changed into rust.