Physical and Chemical Changes

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 melting, freezing, and dissolving.

Front

What is a chemical change?

Back

A chemical change is a process where one or more substances are transformed into new substances with different properties. Examples include rusting, burning, and digestion.

Front

What is a sign that a chemical reaction has occurred?

Back

Signs of a chemical reaction include the formation of a gas, color change, temperature change, and the formation of a precipitate.

Front

Is melting butter for popcorn a chemical or physical change?

Back

Melting butter for popcorn is a physical change because it does not change the chemical composition of the butter.

Front

Which of the following is NOT an example of a physical change?

Back

Rust is NOT an example of a physical change; it is a chemical change.

Front

What happens to the molecules during a physical change?

Back

During a physical change, the arrangement of molecules may change, but their chemical structure remains the same.

Front

What happens to the molecules during a chemical change?

Back

During a chemical change, the bonds between atoms are broken and new bonds are formed, resulting in the creation of new substances.

Front

Is color change always a sign of a chemical change?

Back

No, color change is not always a sign of a chemical change; it can also occur in physical changes.

Front

What is an example of a physical change?

Back

Examples of physical changes include ice melting, water boiling, and paper tearing.

Front

What is an example of a chemical change?

Back

Examples of chemical changes include burning wood, rusting iron, and baking a cake.