Polyatomic ions

Arsenate

AsO4 3-, The arsenate ion is AsO³⁻ ₄. An arsenate is any compound that contains this ion. Arsenates are salts or esters of arsenic acid. The arsenic atom in arsenate has a valency of 5 and is also known as pentavalent arsenic or As(V).

Bromate

BrO3-, A bromate is a chemical compound that contains this ion. Examples of bromatesinclude sodium bromate, (NaBrO. 3), and potassium bromate, (KBrO. 3). Bromatesare formed many different ways in municipal drinking water.

Acetate

C2H3O2-, An acetate is a salt formed by the combination of acetic acid with a base. "Acetate" also describes the conjugate base or ion typically found in aqueous solution and written with the chemical formula C ₂H ₃O⁻

Oxalate

C2O4 2-, Oxalate is a naturally occurring molecule found in abundance in plants and humans. It's not a required nutrient for people, and too much can lead to kidney stones. In plants, oxalate helps to get rid of extra calcium by binding with it. That is why so many high-oxalate foods are from plants.

Cyanide

CN-, cyanide is a chemical compound that contains the group C≡N. This group, known as the cyano group, consists of a carbon atom triple-bonded to a nitrogen atom. In inorganic cyanides, the cyanide group is present as the anion CN−. Salts such as sodium cyanide and potassium cyanide are highly toxic.

Carbonate

CO3 2-, In chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, a polyatomic ion with the formula of CO²⁻ ₃. The name may also refer to a carbonate ester, an organic compound containing the carbonate group C(O-)₂.

Hypochlorite

ClO-, In chemistry, hypochlorite is an anion with the chemical formula ClO⁻. It combines with a number of cations to form hypochlorites, which may also be regarded as the salts of hypochlorous acid. Common examples include sodium hypochlorite and calcium hypochlorite.

Chlorite

ClO2-, Chlorite is a common mineral associated with hydrothermal ore deposits and commonly occurs with epidote, sericite, adularia and sulfide minerals. Chlorite is also a common metamorphic mineral, usually indicative of low-grade metamorphism.

Chlorate

ClO3-, Chlorate is an anion that can enter drinking water from several potential sources, including from hypochlorite or chlorine dioxide disinfectant use, ozone oxidation of hypochlorite or chlorite and source water contamination from pesticide runoff or papermill discharges.

Perchlorate

ClO4-, A perchlorate is a chemical compound containing the perchlorate ion, ClO − 4. . The majority of perchlorates are commercially produced salts. They are mainly used as oxidizers for pyrotechnic devices and to control static electricity in food packaging.

Dichromate

Cr2O7 2-, Dichromate(2-) is a divalent inorganic anion obtained by removal of both protons from dichromic acid. It is a chromium oxoanion and a divalent inorganic anion. It is a conjugate base of a hydrogen dichromate.

Chromate

CrO4 2-, Chromate salts contain the chromate anion, CrO²⁻ ₄. Dichromate salts contain the dichromate anion, Cr ₂O²⁻ ₇. They are oxyanions of chromium in the 6+ oxidation state and are moderately strong oxidizing agents. In an aqueous solution, chromate and dichromate ions can be interconvertible

Dihydrogen Phosphate

H2PO4-, Dihydrogen phosphate or dihydrogenphosphate ion is an inorganic ion with the formula [H₂PO₄]⁻. Its formula can also be written as [PO₂(OH)₂]⁻, which shows the presence of two O-H bonds. Together with hydrogen phosphate, dihydrogen phosphate occurs widely in natural systems.

Hydrogen Carbonate

HCO3-, Hydrogen carbonate, also referred to as bicarbonate, and amphoteric in nature, is an intermediate form in the deprotonation of carbonic acid and a polyatomic anion. Bicarbonate serves a crucial biochemical role in the physiological pH buffering system.

Hydrogen Phosphate

HPO4 2-, Hydrogenphosphate is a phosphate ion that is the conjugate base of dihydrogenphosphate. It has a role as a Saccharomyces cerevisiae metabolite and a cofactor. It is a divalent inorganic anion and a phosphate ion. It is a conjugate base of a dihydrogenphosphate.

Iodate

IO3-, An iodate is a conjugate base of iodic acid. In the iodate anion, iodine is bonded to three oxygen atoms and the molecular formula is IO⁻ ₃. The molecular geometry of iodate is trigonal pyramidal. Iodate can be obtained by reducing a periodate with a sulfide. The byproduct of the reaction is a sulfoxide.

Periodate

IO4-, Periodate is an anion composed of iodine and oxygen. It is one of a number of oxyanions of iodine and is the highest in the series, with iodine existing in oxidation state +7. Unlike other perhalogenates, such as perchlorate, it can exist in two forms: metaperiodate IO⁻ ₄ and orthoperiodate IO⁵⁻ ₆.

Ammonium ion

NH4+, is a positively charged or protonated substituted amines and quaternary ammonium cations (NR + 4. ), where one or more hydrogen atoms are replaced by organic groups. About 80% of the ammonia produced by industry is used in agriculture as fertilizer. Ammonia is also used as a refrigerant gas, for purification of water supplies, and in the manufacture of plastics, explosives, textiles, pesticides, dyes and other chemicals.

Nitrite

NO2-, Nitrite is an intermediate product of the oxidation of ammonia to nitrate. Normally, very little nitrite is present in aquaculture systems. However, nitrite will occasionally accumulate in culture systems due to an imbalance in the nitrification process.

Nitrate

NO3- , Nitrate is a nitrogen oxoanion formed by loss of a proton from nitric acid. Principal species present at pH 7.3. It is a nitrogen oxoanion, a member of reactive nitrogen species and a monovalent inorganic anion.

Peroxide

O2 2-, Peroxides are a group of compounds with the structure R−O−O−R. The O−O group in a peroxide is called the peroxide group or peroxo group. In contrast to oxide ions, the oxygen atoms in the peroxide ion have an oxidation number of −1

Cyanate

OCN-, a salt or ester of cyanic acid.

Hydroxide

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

Phosphite

PO3 3-, A phosphite anion or phosphite in inorganic chemistry usually refers to [HPO₃]²⁻ but includes [H₂PO₃]⁻. These anions are the conjugate bases of phosphorous acid. The corresponding salts, e.g. sodium phosphite are reducing in character.

Phosphate

PO4 3-, In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid H ₃PO ₄. The phosphate or orthophosphate ion [PO ₄]³⁻ is derived from phosphoric acid by the removal of three protons H⁺

MnO4-

Permanganate, permanganate is the general name for a chemical compound containing the manganate(VII) ion, (MnO − 4. ). Because manganese is in the +7 oxidation state, the permanganate(VII) ion is a strong oxidizing agent. The ion has tetrahedral geometry.

Thiosulfate

S2O3 2-, Thiosulfate is an oxyanion of sulfur. The prefix thio- indicates that the thiosulfate ion is a sulfate ion with one oxygen replaced by sulfur. Thiosulfate has a tetrahedral molecular shape with C₃ᵥ symmetry. Thiosulfate occurs naturally and is produced by certain biochemical processes.

Thiocyanate

SCN-, Thiocyanate (also known as rhodanide) is the anion [SCN]−. It is the conjugate base of thiocyanic acid. Common derivatives include the colourless salts potassium thiocyanate and sodium thiocyanate. Organic compounds containing the functional group SCN are also called thiocyanates.

Sulfite

SO3 2-, Sulfites or sulphites are compounds that contain the sulfite ion (or the sulfate(IV) ion, from its correct systematic name), SO 2− 3. . The sulfite ion is the conjugate base of bisulfite. Although its acid (sulfurous acid) is elusive, its salts are widely used.

Sulfate

SO4 2-, Sulfate is a salt that forms when sulfuric acid reacts with another chemical. It's a broader term for other synthetic sulfate-based chemicals you may be concerned about, such as sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES).