Elements, Compounds, and Mixtures

A mixture is a combination of two or more substances that are not chemically bonded. Examples include salad and air.

A compound is a substance formed when two or more elements are chemically bonded together. An example is table salt (NaCl).

An element is a pure substance that cannot be broken down into simpler substances by chemical means. Examples include oxygen (O) and gold (Au).

A homogeneous mixture has a uniform composition throughout, like lemonade, while a heterogeneous mixture has distinct, separate components, like salad.

Lemonade is an example of a homogeneous mixture because it has a uniform composition.

Salad is an example of a heterogeneous mixture because it contains different components that are not uniformly distributed.

As of now, there are 118 known elements in the periodic table.

The chemical formula for water is H2O, which means it is made of two hydrogen atoms and one oxygen atom.

The process of separating a mixture is called filtration, distillation, or chromatography, depending on the method used.

The main characteristic of a compound is that it has a fixed composition and specific properties that are different from the individual elements.