Gasoline

Gasoline

Gasoline makes cars run. This liquid is very important to us. A car’s engine burns gasoline mixed with air. The energy released by burning gasoline turns the car’s wheels and makes the car go.

When the car starts to run out of gas, it’s time to fill up the car’s gas tank at a gas station. When you’re at a gas station, you’re probably standing on top of a huge underground storage tank. The pump brings the gasoline up from the storage tank, and a hose feeds it into the car’s gas tank.

Our world uses huge amounts of gasoline. The United States alone uses about 310 billion gallons (1.2 trillion liters) every year.

WHAT IS GASOLINE?

Gasoline is one of many substances found in oil, a natural liquid that forms deep underground. When this crude oil is pumped out of the ground, it’s a mixture of substances called hydrocarbons. They’re called hydrocarbons because they are made up of chains of the elements hydrogen and carbon. Different hydrocarbons have chains of different lengths.

Gasoline is a lightweight liquid at room temperature, but it becomes a vapor (gas) when warmed up. When gasoline vapor is mixed with oxygen from the air, a spark causes the mixture to burn quickly and give off a lot of heat. That’s what makes gasoline a good engine fuel. A car’s engine turns this heat into energy that turns the wheels.

HOW IS GASOLINE MADE?

Gasoline is separated from crude oil at factories called oil refineries. There are several ways to get the gasoline out. The oldest and simplest way is to boil the crude oil. Gasoline boils at a lower temperature than other parts of crude oil. Gasoline can be separated because it becomes a gas while the rest of the oil remains liquid.

The most common modern method for making gasoline is “cracking.” Longer, heavier hydrocarbon chains can be cracked into the smaller chains that make up gasoline. Gasoline produced by cracking burns more completely and evenly than gasoline produced in other ways. It makes an engine perform better and last longer.

GASOLINE AND AIR POLLUTION

Burning gasoline creates problems. It puts out gases that cause air pollution. These gases also cause global warming. Engineers and scientists are searching for solutions to these problems. Someday you may drive a car that is not powered by gasoline.