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 includes processes like burning, rusting, and digestion.

Front

What happens to iron when it rusts?

Back

When iron rusts, it undergoes a chemical reaction with oxygen and moisture in the air, forming iron oxide, commonly known as rust.

Front

What is a precipitate?

Back

A precipitate is a solid that forms and settles out of a liquid mixture during a chemical reaction.

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

What is an example of a physical change?

Back

Cutting a piece of paper is an example of a physical change because it does not change the chemical composition of the paper.

Front

What is an example of a chemical change?

Back

Burning wood is an example of a chemical change because it transforms the wood into ash, smoke, and gases.

Front

What is the difference between a physical change and a chemical change?

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

Front

What is oxidation?

Back

Oxidation is a chemical reaction that involves the loss of electrons, often associated with the reaction of a substance with oxygen, such as rusting.

Front

What is the law of conservation of mass?

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The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; it is conserved.