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

Verified step by step guidance

1. Identify the nature of aluminium: Aluminium is a chemical element with the symbol Al and atomic number 13.
2. Determine if aluminium is a pure substance or a mixture: Since it is a chemical element, it is composed of only one type of atom.
3. Classify aluminium as a pure substance: Elements are considered pure substances because they cannot be separated into simpler substances by physical or chemical means.
4. Consider the characteristics of mixtures: Mixtures consist of two or more substances physically combined, which can be homogeneous (uniform composition) or heterogeneous (non-uniform composition).
5. Conclude that aluminium is a pure substance, not a mixture, because it consists of only one type of atom and cannot be separated into different components.

Key Concepts

Pure Substances

A pure substance consists of a single type of particle and has a uniform composition throughout. Examples include elements like aluminum 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 composition is uniform (like saltwater), or heterogeneous, where the composition varies (like a salad). The components of a mixture retain their individual properties.

Classification of Matter

Matter can be classified into pure substances and mixtures based on its composition. Understanding this classification helps in identifying materials and predicting their behavior in chemical reactions. For example, knowing that aluminum is a pure substance allows us to infer its consistent properties and behavior in various contexts.