What is the difference between positive divalent iron ions and positive trivalent iron ions

1.Different colors in aqueous solution: positive divalent iron ions are light green in color in aqueous solution; The positive trivalent iron ions are yellow in color in aqueous solution.

2.Positive divalent iron ions are both reducing and oxidizing, and in high school, positive trivalent iron ions are only oxidizing.

3.The positive divalent iron ions undergo complexation reaction with SCN-, and the color remains unchanged. The positive trivalent iron ion SCN- undergoes complexation reaction and is blood-red in color.

4.The reaction phenomenon is different from that of sodium hydroxide solution; The reaction phenomenon of positive divalent iron ions with sodium hydroxide solution is to form a white precipitate, then turn into a gray-green precipitate, and finally form a reddish-brown precipitate. The reaction of positive trivalent iron ions with sodium hydroxide solution forms a reddish-brown precipitate. ‍‍

Positive divalent iron ions.

with two positive charges, positive trivalent with three positive charges. The positive divalent iron ions are blue-green, and the positive trivalent iron ions are yellow-brown.

Positive ferric ions are unstable and can be easily oxidized to form positive ferric ions in weak acid or alkaline aqueous solutions.

Both positive ferric ions and ferric ions are easily hydrolyzed to form ferrous hydroxide.

and iron hydroxide. Among them, iron hydroxide is easy to form colloids.

Divalent iron ion solution light green Trivalent iron ion solution brown yellow Trivalent iron is oxidizing.

Divalent iron ions are ferrous ions, metal cations, and the ion symbol Fe2+.

It is generally light green, has strong reducing properties, and can react with many oxidants, such as chlorine.

oxygen, etc. Therefore, the ferrous ion solution is better to prepare and use, and some iron powder is added to it during storage (iron ions have strong oxidation and can react with iron elements to form ferrous ions) ferrous ions are also oxidized, but the oxidation is relatively weak, and can be replaced with magnesium, aluminum, zinc and other metals.

Chemical properties

The 3-valent compound of iron is relatively stable. Iron ions are 3-valent ions, which are ions obtained by the loss of electrons in the outer shell of iron. In addition to this, the iron atom can also lose two electrons to get ferrous ions.

When iron reacts with elemental sulfur, copper sulfate solution, hydrochloric acid, dilute sulfuric acid, etc., it loses two electrons and becomes 2-valent, while with Cl2, Br2, nitric acid.

and hot concentrated sulphuric acid.

When reacted, it is oxidized to Fe3+.

Iron with oxygen or water vapor.

The Fe3O4 produced by the reaction is often regarded as FeO·Fe2O3

But it is actually a crystal with a trans spinel structure, which is neither a mixture nor a salt. Of these, 1 3 Fe is 2 valent and 2 3 is 3 valent.

Different colors are different for different states:

The 2-valent iron ions in the solution are light green, and the 3-valent iron ions are yellow-green;

When a precipitate is formed, the ferric 2-valent ions are reddish-brown and the ferric 3-valent ions are yellow.

The difference between the two in solution:

The solution containing Fe2+ --- light green.

The solution containing Fe 3+ --- yellow.

Solution containing Cu2+ --- blue.

If both Fe2+ and Fe3+ are present, the yellow color will mask the light green, and the solution will appear yellow. If it also contains Cu 2+, it will be green.

When is the difference between 3-valent iron ions and 2-valent iron ions

Iron loses two electrons when it reacts with sulfur, copper sulfate solution, hydrochloric acid, dilute sulfuric acid, etc., and becomes +2 valence. It reacts with Cl2, Br2, nitric acid and hot concentrated sulfuric acid to be oxidized to Fe3+.

Fe3O4 formed by the reaction of iron with oxygen or water vapor can be regarded as FeO·Fe2O3, of which 1 3 Fe is +2 valence and 2 3 is +3 valence. The 3-valent compound of iron is relatively stable. The oxidation of iron ions is greater than that of copper ions, and iron elements can reduce copper ions, which can naturally reduce iron ions.

How to test for +2 ferric ions and +3 ferric ions:Two test tubes were respectively filled with +2 valence iron ions and +3 valent iron ion solutions, respectively, the KSCN solution was added dropwise, and the +3 ferric ions that immediately turned blood-red were the +2 ferric ions, and the ones that did not change color only turned blood-red after adding the newly made chlorinated water were +2 ferric ions.

The light green solution observed in normal observation must be +2 valence iron ions, and the yellow solution may be +3 valence iron ions.

Divalent iron ions can be detected by utilizing magnetic field detection and ion exchange techniques. Ferrite ions can be detected by using different indicators and chromatographic techniques. Ion resolution techniques can also be used, using mass spectrometers to detect the concentration of different iron ions.