3B-2 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 cutting, dissolving, and changing states (like melting or freezing).

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 the rearrangement of atoms. Examples include rusting, burning, and souring of milk.

Front

Is cutting an apple a physical or chemical change?

Back

Cutting an apple is a physical change because it does not change the chemical composition of the apple.

Front

What happens during a chemical change?

Back

During a chemical change, substances react to form new substances with different properties. This often involves the breaking and forming of chemical bonds.

Front

Is mixing chocolate syrup in milk a physical or chemical change?

Back

Mixing chocolate syrup in milk is a physical change because the syrup and milk retain their original properties and can be separated.

Front

What is an example of a chemical change?

Back

An example of a chemical change is when vinegar is mixed with baking soda, producing carbon dioxide gas.

Front

Is inflating a tire a physical or chemical change?

Back

Inflating a tire is a physical change because it involves changing the volume of air inside the tire without altering the air's chemical composition.

Front

What is an indicator of a chemical change?

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Indicators of a chemical change include color change, temperature change, gas production, and the formation of a precipitate.

Front

Is souring of milk a physical or chemical change?

Back

Souring of milk is a chemical change because it involves the fermentation process that alters the chemical composition of the milk.

Front

What is the difference between physical and chemical changes?

Back

The main difference is that physical changes do not change the chemical composition of a substance, while chemical changes do.