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 change that results in the formation of new chemical substances. It involves a chemical reaction and can be indicated by color change, temperature change, gas production, or precipitate formation.

Front

What happens during cooking an egg?

Back

Cooking an egg is a chemical change because it transforms the proteins in the egg, resulting in a new substance with different properties.

Front

What is an indicator of a chemical change?

Back

Indicators of a chemical change include unexpected color changes, temperature changes, gas production (bubbles), and the formation of precipitates.

Front

What is an example of a new substance forming?

Back

Lighting a match is an example of a new substance forming, as it produces heat, light, and new chemical compounds.

Front

What does bubbling indicate when substances are combined?

Back

Bubbles forming when two or more substances are combined typically indicate a chemical change, as gas is being produced.

Front

What is NOT an indicator of a chemical change?

Back

Bubbles and steam rising from boiling salt water is NOT an indicator of a chemical change; it is a physical change.

Front

What is an unexpected color change?

Back

An unexpected color change is a sign of a chemical change, indicating that a new substance has formed.

Front

What is temperature change in a chemical reaction?

Back

Temperature change during a chemical reaction can indicate that energy is being absorbed or released, which is a sign of a chemical change.

Front

What is the difference between a physical and chemical change?

Back

A physical change does not alter the chemical composition of a substance, while a chemical change results in the formation of new substances.