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

Which of the following is NOT an example of a physical change: crumpled paper, pencil sharpening, shrunken clothing, or rust?

Back

Rust is NOT an example of a physical change; it is a chemical change.

Front

Is the melting of wax a physical change or a chemical change?

Back

The melting of wax is a physical change.

Front

True or False: Change in color is a physical change.

Back

False; change in color is often an indication of a chemical change.

Front

What happens when sugar dissolves in water?

Back

Dissolving sugar in water is an example of a physical change.

Front

Is cutting a log into small pieces a chemical change or a physical change?

Back

Cutting a log into small pieces is a physical change.

Front

What are some indicators of a chemical change?

Back

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

Front

What is an example of a physical change that occurs when water freezes?

Back

When water freezes, it changes from liquid to solid, which is a physical change.

Front

What is an example of a chemical change that occurs when iron rusts?

Back

When iron rusts, it reacts with oxygen in the presence of moisture to form iron oxide, which is a chemical change.