Pure Substances and Mixtures

Front

What is a pure substance?

Back

A pure substance is a material that has a constant composition and consistent properties throughout. It can be an element or a compound.

Front

What is a mixture?

Back

A mixture is a combination of two or more substances where each retains its own properties. Mixtures can be homogeneous or heterogeneous.

Front

Define an element.

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means. It consists of only one type of atom.

Front

Define a compound.

Back

A compound is a pure substance formed when two or more elements are chemically bonded together in a fixed ratio.

Front

What is the difference between a compound and a mixture?

Back

A compound has a chemical formula and fixed composition, while a mixture does not have a chemical formula and can vary in composition.

Front

What is a homogeneous mixture?

Back

A homogeneous mixture is a mixture that has a uniform composition and appearance throughout, such as saltwater.

Front

What is a heterogeneous mixture?

Back

A heterogeneous mixture is a mixture where the components are not uniformly distributed, such as a salad.

Front

What is an example of a compound?

Back

Water (H2O) is an example of a compound, consisting of two hydrogen atoms and one oxygen atom.

Front

What is an example of an element?

Back

Oxygen (O) is an example of an element, consisting of only oxygen atoms.

Front

What is an example of a mixture of compounds?

Back

Air is an example of a mixture of compounds, containing nitrogen, oxygen, carbon dioxide, and other gases.