A base anhydride is an oxide of a

chemical element A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species. Unlike chemical compounds, chemical elements cannot be broken down into simpler sub ...

from group 1 or 2 (the alkali metals and

alkaline earth metal The alkaline earth metals are six chemical elements in group 2 of the periodic table. They are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).. The elements have very similar properties: they are all ...

s, respectively). They are obtained by removing

water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...

from the corresponding

hydroxide Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. I ...

base. If water is added to a base anhydride, a corresponding hydroxide

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...

can be re-formed. Base anhydrides are not Brønsted–Lowry bases because they are not proton acceptors. However, they are Lewis bases, because they will share an electron pair with some

Lewis acids A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any spe ...

, most notably

acidic oxide An acidic oxide is an oxide that either produces an acidic solution upon addition to water, or acts as an acceptor of hydroxide ions effectively functioning as a Lewis acid. Acidic oxides will typically have a low pKa and may be inorganic or org ...

s.Principles of Modern Chemistry, 7th Edition. David Oxtoby, H. P. Gillis,

Alan Campion Alan Campion is an American chemist, currently the Dow Chemical Company Endowed Professor and University Distinguished Teaching Professor at the University of Texas at Austin. Education *BA, New College of Florida, 1972 *C.Phil., UCLA ...

. Published by Cengage Learning. Page 675-676. They are potent alkalis and will produce alkali burns on skin, because their affinity for water (that is, their affinity for being slaked) makes them react with

body water In physiology, body water is the water content of an animal body that is contained in the tissues, the blood, the bones and elsewhere. The percentages of body water contained in various fluid compartments add up to total body water (TBW). This ...

Examples

* Quicklime (

calcium oxide Calcium oxide (CaO), commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline, crystalline solid at room temperature. The broadly used term "''lime''" connotes calcium-containing inorganic ...

) is a base anhydride. It reacts with skin to become hydrated lime ( calcium hydroxide), which is a strong base, chemically akin to

lye A lye is a metal hydroxide traditionally obtained by leaching wood ashes, or a strong alkali which is highly soluble in water producing caustic basic solutions. "Lye" most commonly refers to sodium hydroxide (NaOH), but historically has been u ...

References

{{reflist Acid–base chemistry

Examples

See also

References