What are compounds formed by?

Compounds are formed when elements chemically bond together, resulting in the formation of a new substance with distinct chemical and physical properties. This process involves the sharing or transferring of electrons between atoms, leading to the creation of molecules. For instance, water (H2O) is a compound formed by the chemical bonding of hydrogen and oxygen atoms. These chemical bonds can be covalent or ionic, depending on how the atoms interact.

The other options do not accurately describe the formation of compounds. Physical combinations of elements, for example, would refer to mixtures rather than true chemical compounds. Similarly, mixtures of different compounds do not result in a single new compound but rather retain the individual properties of each constituent. Lastly, while natural minerals and resources can contain compounds, they do not define the process of how compounds are formed on a chemical level.