8 NC Check-In Review Physical Science

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. Examples include boiling water and melting wax.

Front

What is a chemical change?

Back

A chemical change is a change that results in the formation of new chemical substances. Examples include rusting iron and baking a cake.

Front

What happens to water molecules during boiling?

Back

During boiling, water molecules move faster and move farther apart as they absorb heat.

Front

What does the Law of Conservation of Mass state?

Back

The Law of Conservation of Mass states that during a chemical reaction, the total amount of matter stays the same; matter is neither created nor destroyed.

Front

If a chemical reaction starts with 6 atoms of carbon, how many should be in the products?

Back

There should be 6 atoms of carbon in the products, as matter is conserved.

Front

What is the expected number of atoms after a chemical reaction if you start with 23 atoms?

Back

You would expect to have 23 atoms remaining after the reaction, as matter is conserved.

Front

What is an example of a physical change?

Back

An example of a physical change is freezing water.

Front

What is an example of a chemical change?

Back

An example of a chemical change is burning coal.

Front

How do molecules behave when heat is absorbed?

Back

When heat is absorbed, molecules move faster and tend to move farther apart.

Front

What does a balanced chemical equation represent?

Back

A balanced chemical equation represents that the number of atoms of each element is the same on both sides of the equation, satisfying the Law of Conservation of Mass.