What is meant by matter?

• A. A substance with a definite chemical composition.
• B. Anything that occupies space and has weight.
• C. A force that interacts with a surface.
• D. The energy contained in a system.

Answer: (B)

Matter is anything that has mass and takes up space. In everyday science, weight is the gravitational force on mass, so objects with mass have weight in Earth conditions. Because of that, describing matter as anything that occupies space and has weight fits well with how we commonly understand matter: it includes solids, liquids, gases, and even mixtures, all of which occupy space and have mass (and thus weight under gravity).

The other ideas don’t describe matter. A pure substance with a definite chemical composition is a specific kind of matter, but matter also includes mixtures and substances that don’t have to be perfectly fixed in composition. A force that interacts with a surface is a description of a physical interaction, not matter. The energy contained in a system is energy, not matter. Hence, the statement that best matches the everyday definition of matter is the one about occupying space and having weight.