A Lewis acid is an electron pair acceptor; a Lewis base is an electron pair donor. Conjugate Acids and Bases The concept of conjugate acids and bases is best understood by considering what happens when a substance behaves as a Brønsted–Lowry acid or a Brønsted–Lowry base. By reversing the reaction in which a substance acts as a proton donor, we see that the product is itself a proton acceptor. It is thus a base, or more specifically, it is the conjugate base of the original acid. Similarly, when a substance behaves as a Brønsted–Lowry base, the product is a proton donor. It is thus the conjugate acid of the original base. In summary, a conjugate base is the species that remains after a Brønsted–Lowry acid donates a proton, and a conjugate acid is the species that forms when a Brønsted–Lowry base accepts a proton. Glossary A brief glossary of terms relating the properties of atoms /molecules to acids and bases: Atomic charge is the charge (usually a fraction) that an atom or group of atoms carries when it is in a molecule. All of the atomic charges in a species must add up to the charge on that species.

Brgnsted- : Lowry acid-base reaction is the transfer of a proton from a proton donor to a proton acceptor … in which a proton is transferred from a proton donor to a proton acceptor (20.1) Brdnsted-Lowry base any … act as a proton donor is a Brénsted-Lowry acid. Any mol- ecule or ion that can act as a proton acceptor

Brønsted–Lowry acid–base theory The Brønsted–Lowry acid–base theory (also called proton theory of acids and bases)[1] is one of the two main definitions of acids and bases in modern chemistry, alongside the Lewis acid-base theory.[2] Johannes Nicolaus Brønsted and Thomas Martin Lowry developed the theory in 1923.[3][4] A chemical is a Brønsted–Lowry acid if it can give a hydrogen ion to another chemical,[5] and a chemical is a Brønsted–Lowry base[6] if it can take a hydrogen ion from another chemical. When an acid loses a hydrogen, it becomes its conjugate base, and when a base gains a hydrogen ion, it becomes its conjugate acid.[7] According to these definitions, an acid-base reaction always takes the form - AH + B → A− + BH+ where AH is a Brønsted-Lowry acid, B is a Brønsted-Lowry base, A− is the acid's conjugate base, and BH+ is the base's conjugate acid. Comparison to Arrhenius theory The Brønsted-Lowry theory (adds to or) expands the Arrhenius theory to understand amphoteric compounds, compounds like ammonia that act like a base without containing hydroxide, and solvents other than water.

An acid is a molecule or ion capable of either donating a proton (i.e. hydrogen cation, H+), known as a Brønsted–Lowry acid, or forming a covalent bond An acid is a molecule or ion capable of either donating a proton (i.e. hydrogen cation, H+), known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid. The first category of acids are the proton donors, or Brønsted–Lowry acids. In the special case of aqueous solutions, proton donors form the hydronium ion H3O+ and are known as Arrhenius acids. Brønsted Moder…