What occurs when a metal-oxide is dissolved in water?

When a metal-oxide is dissolved in water, it typically forms an alkali. This occurs because metal oxides, especially those of alkali and alkaline earth metals, can react with water to produce hydroxide ions. For example, sodium oxide (a metal-oxide) reacts with water to form sodium hydroxide, which is an alkali.

Alkalis are characterized by their ability to increase the concentration of hydroxide ions (OH⁻) in solution, resulting in a basic (alkaline) solution. This property of metal oxides to produce hydroxides upon dissolution in water is crucial in various chemical processes and applications, particularly in industries related to manufacturing and water treatment.

In contrast, acids are typically formed from non-metal oxides or by the reaction of metals with acids rather than through the dissolution of metal oxides in water. Salts, on the other hand, are often produced from the neutralization reactions between acids and bases. The notion that the metal-oxide might remain unchanged in water would apply to certain metal-oxides that are insoluble, but those do not fit the expectation of common reactions involving dissolvable metal-oxides. Thus, the formation of an alkali is the most accurate outcome for the