Here's why:

* Mixture: A combination of two or more substances where each substance retains its own chemical identity. The components can be separated by physical means like filtration, distillation, or evaporation.

* Chemical bond: A force of attraction between atoms that holds them together in a molecule.

Examples of mixtures:

* Salt and pepper: The salt and pepper grains remain separate, even when mixed.

* Sand and water: The sand particles and water molecules are not chemically bound.

* Air: A mixture of gases like nitrogen, oxygen, and carbon dioxide.

Let me know if you have any other questions!