acid salt



Acid salts are a class of salts that produce an acidic solution after being dissolved in a
solvent A solvent (s) (from the Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) a ...
. Its formation as a substance has a greater electrical conductivity than that of the pure solvent. An acidic solution formed by acid salt is made during partial neutralization of diprotic or polyprotic acids. A ''half-neutralization'' occurs due to the remaining of replaceable
hydrogen Hydrogen is the 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 element ...
atom Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons. Every solid, liquid, g ...
s from the partial dissociation of weak acids that have not been reacted with hydroxide ions () to create water molecules.

Acidic solution and examples of acid salts

Acid-base property of the resulting solution from a neutralization reaction depends on the remaining salt products. A salt containing reactive cations undergo
hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolys ...
by which they react with water molecules, causing
deprotonation Deprotonation (or dehydronation) is the removal (transfer) of a proton (or hydron, or hydrogen cation), (H+) from a Brønsted–Lowry acid in an acid–base reaction.Henry Jakubowski, Biochemistry Online Chapter 2A3, https://employees.csbsju. ...
of the conjugate acids.
For example, the acid salt ammonium chloride is the main species formed upon the ''half neutralization'' of ammonia in hydrochloric acid solution: :NH3_\ +\ HCl_ -> NH4Cl_

Use in food

Acidic salts are often used in foods as part of leavening agents. In this context, the acid salts are referred to as "leavening acids." Common leavening acids include cream of tartar and monocalcium phosphate. An acidic salt can be mixed with an alkali salt (such as sodium bicarbonate or baking soda) to create baking powders which release
carbon dioxide Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...
. Leavening agents can be slow-acting (e.g. sodium aluminum phosphate) which react when heated, or fast-acting (e,g, cream of tartar) which react immediately at low temperatures. Double-acting baking powders contain both slow- and fast-acting leavening agents and react at low and high temperatures to provide leavening rising throughout the baking process. Disodium phosphate, , is used in foods and monosodium phosphate, , is used in animal feed, toothpaste and evaporated milk.

Intensity of acid

An acid with higher value dominates the chemical reaction. It serves as a better contributor of protons (). A comparison between the and indicates the acid-base property of the resulting solution by which: # The solution is acidic if . It contains a greater concentration of ions than concentration of ions due more extensive of cation hydrolysis compared to that of anion hydrolysis. # The solution is alkali if . Anions hydrolyze more than cations, causing an exceeding concentration of ions. # The solution is expected to be neutral only when . Other possible factors that could vary pH level of a solution are the relevant equilibrium constants and the additional amounts of any base or acid. For example, in ammonium chloride solution, is the main influence for acidic solution. It has greater value compared to that of water molecules; of is , and of is . This ensures its deprotonation when reacting with water, and is responsible for the pH below 7 at room temperature. will have no affinity for nor tendency to hydrolyze, as its value is very low ( of is ).Lower, S.K., (1999). Introduction to acid-base chemistry. Chem1 General Chemistry Text. Retrieved from Hydrolysis of ammonium at room temperature produces: :NH4+_\ + H2O_ <=> NH3_\ + H3O+_ : K_\mathrm = \frac = \frac : K_\mathrm = \frac = \times 10^

See also

* Alkali salt *
Salt (chemistry) In chemistry Chemistry is the scientific study of the properties and behavior of matter. It is a natural science that covers the elements that make up matter to the compounds made of atoms, molecules and ions: their composition, ...
* Oxoacid *
Sodium bicarbonate Sodium bicarbonate ( IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda, is a chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular ent ...
* Sodium bisulfate * Disodium phosphate * Monosodium phosphate


{{Use dmy dates, date=March 2018 Salts Acids