Car burns gasoline
Evidence that substances changed (or not)
The combustion of gasoline in a car engine involves a chemical reaction where the hydrocarbons in gasoline react with oxygen to produce carbon dioxide, water, and heat. This chemical reaction results in a physical change in the gasoline, as it is broken down and converted into different substances.
The evidence that substances have changed during this process includes the visible exhaust emissions (carbon dioxide and water vapor), the heat produced by the engine, and the decrease in the volume of gasoline in the fuel tank. Additionally, the combustion process releases energy that is used to power the vehicle, further supporting the idea that a chemical change has occurred.
Overall, the evidence clearly indicates that a chemical change occurs when gasoline is burned in a car engine.