Oxides that are described as basic in nature are metal oxides. These oxides are formed by the combination of a metal with oxygen. Basic oxides typically exhibit properties of bases, as they can react with acids to form salts and water through acid-base neutralization reactions. Basic metal oxides often contain electropositive metal cations, which readily donate electrons or accept protons. Examples include sodium oxide (Na₂O) and calcium oxide (CaO). These oxides contribute to the alkaline character of solutions when dissolved in water, as they generate hydroxide ions (OH⁻) through interaction with water molecules.