This PowerPoint document discusses combustion reactions and provides examples of how combustion works in engines. It defines combustion as a reaction between a fuel and oxidant that produces heat or heat and light. It explains the fire triangle of oxygen, heat, and fuel and how the cooktop stove exemplifies this. It then discusses combustion engines, how they work by mixing fuel and air to create combustion, and provides an example of cheating in NASCAR to illegally increase engine performance.