What are the differences in properties between elements, compounds, and mixtures?

Elements are pure substances with one type of atom, compounds are chemically bonded substances with two or more atoms, and mixtures are physically combined substances.

Elements are the simplest form of matter that cannot be broken down into simpler substances by chemical means. They are made up of one type of atom and are represented by chemical symbols. For example, hydrogen (H), oxygen (O), and carbon (C) are all elements. Each element has unique properties such as melting point, boiling point, and density, which are determined by the structure of its atoms.

Compounds, on the other hand, are substances formed when two or more elements chemically combine in a fixed ratio. The properties of a compound are different from the properties of its constituent elements. For instance, water (H2O) is a compound formed by the chemical combination of hydrogen and oxygen. It has different properties from hydrogen and oxygen. For example, water is a liquid at room temperature, while hydrogen and oxygen are gases. Also, compounds cannot be separated into their constituent elements by physical means, but only by chemical reactions.

Mixtures are combinations of two or more substances that are not chemically combined. The substances in a mixture retain their individual properties and can be present in any proportion. For example, air is a mixture of several gases including nitrogen, oxygen, and carbon dioxide, each retaining its own properties. Mixtures can be homogeneous (uniform composition) or heterogeneous (non-uniform composition). Unlike compounds, the components of a mixture can be separated by physical means such as filtration, evaporation, or distillation.

In summary, elements, compounds, and mixtures differ in their composition and the way their constituent parts are combined. Elements consist of one type of atom, compounds are made of two or more types of atoms chemically combined, and mixtures are physical combinations of two or more substances.