Physical and Chemical Changes

Front

What is a sign that a chemical reaction has occurred?

Back

Formation of a gas, change in color, temperature change, or formation of a precipitate.

Front

Is change in color a physical change?

Back

No, change in color is typically a sign of a chemical change.

Front

What type of change is melting butter for popcorn?

Back

Physical change.

Front

Which of the following is NOT an example of a physical change: rust, melting ice, boiling water, or dissolving sugar?

Back

Rust is a chemical change.

Front

What is a chemical change?

Back

A change where one or more new substances are created.

Front

What is a physical change?

Back

A change that does not alter the chemical composition of a substance.

Front

Give an example of a chemical change.

Back

Burning wood, rusting iron, or baking a cake.

Front

What happens to the molecules during a physical change?

Back

The molecules may change their state or appearance but remain the same substance.

Front

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

Back

A physical change affects the form of a chemical substance, but not its chemical composition; a chemical change results in the formation of new substances.

Front

Is freezing water a physical or chemical change?

Back

Physical change.