Complete the statement.
During this chemical reaction, the car engine becomes ().
colder warmer
When a chemical reaction absorbs or releases thermal energy, the reaction causes a change in temperature. Read the passage about a chemical reaction that absorbs or releases thermal energy. Then, follow the instructions below.
The gasoline used in cars today is a mixture of over 1,000 different substances. One of these substances is isooctane (C8H18). In a car engine, isooctane reacts with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O). During the reaction, a large amount of thermal energy is released into the surroundings. This thermal energy is used to power the car.
During a chemical reaction, thermal energy is absorbed or released as heat. This transfer of thermal energy changes the temperature of the reaction's surroundings. The surroundings are everything around the reaction, such as the solution that the reaction takes place in or the air nearby.
Some reactions release thermal energy into the surroundings. This thermal energy is converted from chemical energy, which is provided by the molecules in the reaction. As the thermal energy moves out of the reaction and into the surroundings, the temperature of the surroundings increases.
Some reactions absorb thermal energy from the surroundings. This thermal energy is converted into chemical energy during the reaction. As the thermal energy moves out of the surroundings and into the reaction, the temperature of the surroundings decreases.
To determine whether the car engine becomes warmer or colder, look for the text that describes the movement of thermal energy during the reaction.The gasoline used in cars today is a mixture of over 1,000 different substances. One of these substances is isooctane (C8 H18). In a car engine, isooctane reacts with oxygen (O2) to produce carbon dioxide (CO2) and water (H2 O). During the reaction, a large amount of thermal energy is released into the surroundings. This thermal energy is used to power the car.The underlined text tells you that thermal energy is released into the surroundings. Because thermal energy moves out of the reaction and into the surroundings, the temperature of the surroundings increases.The surroundings include the car engine that the reaction takes place in. So, the car engine becomes warmer.