Basic salt, also called an alkali salt, contains a basic ion and is used to form basic compounds. They are formed from a base or hydroxide where hydrogen has been replaced or partially replaced with a negative, an acid or a radical element. Alkali salts are formed from insoluble hydroxide compounds of alkali metals or alkali earth metals. In order to be considered a basic salt, the compound needs to include hydroxide and other anions.
The precipitation method is used to create a basic salt out of its original context. Precipitation is where a solid is created within a liquid or another solid. This effect is achieved by using chemical processes such as carbon dioxide washes. The process of precipitation is often used to create pigments. Salt is often a byproduct of the desalination process when water is treated.
White lead is an early example of a widely-used basic salt. It was an important element used to create lead paint and a cosmetic known as a Venetian Ceruse. A major problem with white lead is its toxicity. This led to the product being banned by many nations across the world. As a consequence, it is used less often by artists.
Another basic salt is calcium carbonate, which is used as an agricultural lime. The base for this salt is found in rocks such as chalk, limestone and marble, where it is often the cause of hard water. It can also be found in the shells of snails, crabs and eggs. Calcium carbonate is created by calcining calcium oxide, then mixing it with water to produce calcium hydroxide. This is then mixed with carbon dioxide.
Potassium cyanide is a more dangerous basic salt. It forms as a colorless crystalline structure resembling sugar granules. It is highly soluble in water and is used by insect collectors as a quick killing method and one that does not damage the specimen being collected. It is created by mixing hydrogen cyanide with potassium hydroxide.
Sodium silicate is a basic salt used in cements and as a natural fire protector. Also called water glass or liquid glass, it is created by mixing sodium carbonate with silicon dioxide. As a result, it produces sodium silicate and carbon dioxide.
Cleaning products such as bleach are being made more ecologically- and environmentally-friendly by using a basic salt called sodium percarbonate. It can also be used as an oxidizing agent in laboratory experiments. Sodium percarbonate is created by mixing sodium carbonate with hydrogen peroxide. The resulting mixture is then crystallized.