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 changes the chemical composition of the original substance. Examples include rusting, burning, and digestion.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Front

Give an example of a physical change.

Back

An example of a physical change is ice melting into water.

Tags

NGSS.MS-PS1-4

Front

Give an example of a chemical change.

Back

An example of a chemical change is the burning of wood, which produces ash and smoke.

Tags

NGSS.MS-PS1-2

Front

What are indicators of a chemical change?

Back

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

Tags

NGSS.MS-PS1-2

Front

What happens to the molecules during a physical change?

Back

During a physical change, the arrangement of molecules may change, but the molecules themselves remain the same.

Front

What happens to the molecules during a chemical change?

Back

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

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Front

Is dissolving sugar in water a physical or chemical change?

Back

Dissolving sugar in water is a physical change because the sugar can be recovered by evaporating the water.

Front

Is burning paper a physical or chemical change?

Back

Burning paper is a chemical change because it produces new substances such as ash and gases.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; the total mass of the reactants equals the total mass of the products.

Tags

NGSS.MS-PS1-5