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. Examples include rusting, burning, and cooking.

Front

What are signs of a chemical reaction?

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 ice a physical or chemical change?

Back

Melting ice is a physical change because it changes from solid to liquid without altering its chemical composition.

Front

What happens during a chemical change?

Back

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

Front

Is rusting of iron a physical or chemical change?

Back

Rusting of iron is a chemical change because it forms a new substance, iron oxide.

Front

What is an example of a physical change?

Back

An example of a physical change is chopping wood or melting butter.

Front

What is an example of a chemical change?

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An example of a chemical change is baking a cake or burning wood.

Front

What does it mean if a substance undergoes a change in color?

Back

A change in color often indicates a chemical change, as new substances with different properties are formed.

Front

What is the difference between a physical change and a 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.