G6_Chemical Reactions-approaching-03

Think about what happens when you start a car’s engine. You hear the engine roar with power. Do you ever wonder what supplies that power that causes a car’s motion? A car owes its potential to move to a chemical reaction. This reaction occurs within the car’s engine. Just like you get your fuel from eating food, a car gets its energy from gasoline. Gasoline is a chemical compound that is very reactive.

When the temperature of gasoline reaches its vapor point, it reacts with oxygen. The reaction creates a huge amount of heat. It also produces a byproduct called carbon dioxide (CO₂), a gas. The heat produced by the reaction heats the surrounding air, causing it to expand. The expanding air is what pushes down the pistons in the car’s engine causing the car to move.

The CO₂ that is emitted through the car’s exhaust pipe. This gas is evidence that a chemical reaction took place. Another piece of evidence that indicates a chemical reaction happened is that it cannot be reversed. The CO₂ gas, heat, and air cannot be combined to make gasoline. In a typical car, the chemical reaction between gasoline and oxygen provides the energy to get the car moving. Gasoline is one type of fuel used in engines. As you will learn, it is not the only kind.

In Florida, the Don Garlit Museum may have you questioning if it is really a car museum. Maybe it is really a museum housing horizontally launched missiles. Don Garlit built and drove some of the fastest dragsters of all time. In fact, he still holds the land speed record of 318.54 mph in just 4.76 seconds in the quarter mile. The dragsters do not run on traditional gasoline like your family car.

Instead, dragsters burn nitromethane. This fuel type increases the speed of the car. Nitromethane is a bit like gasoline, except oxygen is added to the fuel. This helps to speed up the reaction rate and release more energy. Normally, engines need to pull in air from outside of the engine. It is this outside air that is needed to supply the oxygen needed for the reaction. Not so with nitromethane. Some of the needed oxygen is already in the fuel. This mixture of chemicals increases the amount of readily available oxygen. Having the ready supply of oxygen increases the rate of the chemical reaction inside the dragster’s engine.