Unit 1 Chemistry Test Review

Front

What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. It can often be reversed, such as ice melting into water.

Front

What is a phase change?

Back

A phase change is the transition of a substance from one state of matter to another, such as solid to liquid (melting), liquid to gas (evaporation), or gas to solid (deposition).

Front

Define a mixture.

Back

A mixture is a combination of two or more substances that are not chemically combined, meaning they retain their individual properties.

Front

How does temperature relate to molecular movement?

Back

The temperature of a substance is directly related to the average kinetic energy of its molecules; as the temperature increases, the molecules move faster.

Front

What happens to the temperature when molecular movement decreases?

Back

When molecular movement decreases, the temperature of the substance also decreases, indicating lower kinetic energy.

Front

What is the difference between a physical change and a chemical change?

Back

A physical change involves a change in physical properties without altering the chemical composition, while a chemical change results in the formation of new substances with different chemical properties.

Front

What are the three states of matter?

Back

The three states of matter are solid, liquid, and gas, each characterized by different molecular arrangements and energy levels.

Front

What is the process of melting?

Back

Melting is the process by which a solid turns into a liquid when it absorbs heat energy.

Front

What is evaporation?

Back

Evaporation is the process by which a liquid turns into a gas at temperatures below its boiling point, typically occurring at the surface of the liquid.

Front

What is condensation?

Back

Condensation is the process by which a gas turns into a liquid, usually when it cools down and loses energy.