The difference between total iron, trivalent iron, and divalent iron

The differences between total iron, trivalent iron, and divalent iron are mainly reflected in the following aspects:

Conceptual meaning

• Total ironIt refers to the total amount of all forms of iron elements in the sample, including iron in different valence states such as divalent iron and trivalent iron, as well as iron that may combine with other substances. For example, when analyzing the iron content in a certain ore, total iron is the sum of all iron elements in the ore

• ferric iron: is an ion formed by the loss of three electrons from an iron atom, with the chemical symbolIt usually exists in the form of compounds, such as ferric chlorideIron sulfateWait

• ferrous ironIron ion, also known as ferrous ion, is an ion formed by the loss of two electrons from an iron atom. The ion symbol isCommon compounds include ferrous sulfateFerrous chlorideWait

physical properties

• colorTrivalent iron ions generally appear brownish yellow in aqueous solutions, such as ferric chloride solutions; The solution of divalent iron ions is usually light green, like a sulfuric acid ferrous solution

• solubilityDivalent iron ions are more easily dissolved in aqueous solutions compared to trivalent iron ions, so in nutrition, ferrous ions are often used to supplement the iron element in the human body

chemical properties

• Redox propertyDivalent iron ions have strong reducibility and are easily oxidized to trivalent iron ions. For example, in air, the solution of divalent iron compounds tends to gradually turn yellow because divalent iron is oxidized to trivalent iron by oxygen in the air; Trivalent iron ions have oxidizing properties and are easily reduced to divalent iron ions. For example, ferric chloride solution can react with iron powder to produce ferrous chloride

• stabilityTrivalent iron compounds are more stable than divalent iron compounds. In aqueous solution, trivalent iron ions are prone to hydrolysis reactions, resulting in the precipitation of iron hydroxide

Biological activity and nutritional significance

• Absorption methodDivalent iron is more easily absorbed by the human body and can be directly absorbed through the small intestinal mucosa into the bloodstream, thereby participating in various physiological activities of the human body; Trivalent iron needs to be reduced to divalent iron before it can be absorbed by the human body, so when supplementing iron in nutrition, the bioavailability of ferrous salts is higher

• physiological functionDivalent iron is an important component of hemoglobin, involved in the transportation and storage of oxygen, and crucial for maintaining normal respiratory function in the human body; It is also a cofactor for many enzymes, involved in important biological processes such as cellular respiration and DNA synthesis. Trivalent iron has relatively little effect in living organisms, but can act as an oxidant in certain specific biochemical reactions.