Classify each of the following as a pure substance or a mixture. If a mixture, indicate whether it is homogeneous or heterogeneous: a. gasoline vapor,

Key Concepts

Pure Substances

A pure substance consists of a single type of particle and has a uniform composition throughout. Examples include elements like oxygen and compounds like water. Pure substances have distinct physical and chemical properties that do not change regardless of the sample size.

Mixtures

A mixture contains two or more different substances that are physically combined but not chemically bonded. Mixtures can be classified as homogeneous, where the components are evenly distributed (like saltwater), or heterogeneous, where the components remain distinct (like a salad).

Homogeneous vs. Heterogeneous Mixtures

Homogeneous mixtures have a consistent composition throughout, making it difficult to distinguish individual components, while heterogeneous mixtures have visibly different substances or phases. The classification affects how mixtures behave and can be separated, influencing their applications in chemistry and industry.