Ionic nature of metal oxides:
Metal oxides are compounds composed of a metal atom and an oxygen atom. The nature of the bonding between the metal and oxygen determines the type of oxide and its properties. Metal oxides are generally ionic in nature.

Explanation:
Ionic bonding occurs between a metal and a non-metal. In the case of metal oxides, the metal atoms transfer electrons to the oxygen atoms, resulting in the formation of positively charged metal ions (cations) and negatively charged oxygen ions (anions).

The metal ions are typically cations because metals tend to lose electrons to attain a stable electron configuration. This electron loss results in the formation of a positively charged ion. For example, in the formation of sodium oxide (Na2O), sodium (Na) loses one electron to become a sodium ion (Na+) with a +1 charge.

On the other hand, the oxygen atoms tend to gain electrons to achieve a stable electron configuration. This electron gain results in the formation of negatively charged ions. For example, in the formation of sodium oxide, oxygen (O) accepts two electrons to become an oxide ion (O2-) with a -2 charge.

The oppositely charged metal and oxygen ions are held together by electrostatic forces of attraction, forming an ionic bond. This bond is strong and non-directional, resulting in a regular repeating pattern of ions in a crystal lattice structure.

Ionic compounds, including metal oxides, typically have high melting and boiling points due to the strong electrostatic forces between the ions. They are also usually solid at room temperature and have a crystalline structure.

In summary, metal oxides are ionic in nature because they are composed of positively charged metal ions and negatively charged oxygen ions held together by strong electrostatic forces. This ionic bonding leads to the characteristic properties of metal oxides, such as high melting points and crystalline structures.