Physical and Chemical Changes, Classification of Matter

Front

What is a homogeneous mixture?

Back

A mixture that contains two or more substances blended evenly throughout, such as saltwater.

Front

What is a physical change?

Back

A change that alters the form or appearance of a substance but does not change its chemical composition, such as melting ice.

Front

What is a chemical change?

Back

A change that results in the formation of new chemical substances, such as burning wood.

Front

What happens during a physical change?

Back

The matter begins and ends as the same substance, like breaking a glass.

Front

What is an example of a chemical change?

Back

Cooking eggs, which changes the structure of the proteins.

Front

What is a solution?

Back

A homogeneous mixture with particles so small they cannot be seen without a microscope, like sugar dissolved in water.

Front

What distinguishes a heterogeneous mixture from a homogeneous mixture?

Back

A heterogeneous mixture contains visibly different substances or phases, like a salad.

Front

What is an element?

Back

A pure substance that cannot be broken down into simpler substances by chemical means, such as oxygen.

Front

What is a compound?

Back

A substance formed when two or more elements are chemically bonded together, like water (H2O).

Front

What is the law of conservation of mass?

Back

In a chemical reaction, matter is neither created nor destroyed; it is conserved.