Classify each of the following as a pure substance or a mixture. If a mixture, indicate whether it is homogeneous or heterogeneous: (b) sugar crystals

Key Concepts

Pure Substances

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

Mixtures

Mixtures are combinations of two or more substances that retain their individual properties. They can be classified as homogeneous, where the components are evenly distributed (like saltwater), or heterogeneous, where the components are not uniformly distributed (like a salad).

Homogeneous vs. Heterogeneous Mixtures

Homogeneous mixtures have a consistent composition throughout, making it difficult to distinguish the individual components. In contrast, heterogeneous mixtures contain visibly different substances or phases, allowing for easy identification of the separate components. Understanding this distinction is crucial for classifying mixtures correctly.