Basic anhydrides are chemical compounds formed by the reaction of a metal oxide with water, resulting in a basic solution. They typically consist of metal ions combined with oxygen, and they can react with acids to produce salts and water. Common examples include sodium oxide and calcium oxide. These compounds are important in various industrial processes, such as the production of cement and the manufacture of glass. Basic anhydrides can also be used in agriculture to improve soil pH and enhance nutrient availability for plants.