Chemical oxidation reaction, what is the oxidation reaction

Fe2+ is converted into Fe3+, the valence increases, as a reducing agent, is oxidized, it is necessary to add a strong oxidant Chlorine Bromine Hydrogen Peroxide Nitric acid and other Fe3+ are converted into Fe2+, the valency is reduced, as an oxidant, it is reduced, it is also necessary to add a stronger reducing agent (weak reducing agent is not good), iodine ions, sulfur ions, sulfite Because Fe3+ itself is a strong oxidant, to react, the oxidant oxidation is greater than that of the oxidation product O( O

Strength is a relative concept, if you want to oxidize a substance, and the oxidation reaction occurs, you must use a substance that is stronger than its oxidation (oxidation potential). Converted from Fe2+ to Fe3+, generally stronger than oxygen, Fe3+ is converted into Fe2+, with weak reduction, it may be to prevent the reducing agent from being too strong to form Fe elemental, probably understood in this way.

Fe2+ is more difficult to oxidize into Fe3+, so a strong oxidant should be used, correspondingly, you can think about this truth: since a substance is more difficult to oxidize, it means that the substance "likes" to be in the reduced state, in other words, if it has been oxidized, it is easier to reduce. Therefore, the conversion of Fe3+ to Fe2+ only requires the use of a weak reducing agent.

This truth can be generalized to many aspects, and life is full of this kind of truth. For example, if you want to get someone who wants to be a writer but doesn't want to be a doctor, it is of course more difficult, and you have to use many means to achieve the goal; However, after he has reluctantly agreed to study medicine, if you mobilize him to give up medicine and switch to literature, it will be relatively easy, hehe.

Chemistry is just like the real world, you know this! The most basic reaction in chemistry is to force weakness. Fe3+ itself is a strong oxidant, if you want to get it, you need to use a stronger oxidant, the knowledge point is that the oxidation of the oxidant is stronger than the oxidation product.

Why is Fe3+ converted to Fe2+ using a weak reducing agent? The reason is very simple, the strong reducing agent can reduce it to iron element, and the result is not Fe2+. That's what I tell my students, do you understand?!

Conversion of Fe to Fe2+ with a weak oxidant is sufficient, while conversion from Fe2+ to Fe3+ is more difficult, so a strong oxidant is required. In the same way, Fe3+ is converted to Fe2+ with a weak reducing agent.

It's all.

The extranuclear electron configuration of Fe is 2,8,14,2 which is relatively unstable and easily oxidized.

Fe2+ is the most stable at 2, 8, 14

So it's more difficult to turn something stable into an unstable state (Fe3+) 2,8,13 and you need to use a strong oxidant.

And to turn an unstable state into a stable state is simpler to use a weak reducing agent.

Of course, there must be electron transfer in the oxidation reaction, and new substances must be generated. In this case, it must be a chemical reaction.

Oxidation is a chemical reaction between a substance and oxygen, in which oxygen is provided. The effect of electron loss in matter is called oxidation; On the contrary, the action of gaining electrons is called reduction. Oxidation reaction in the narrow sense refers to the combination of substances and oxidation; A reduction reaction is the action by which a substance loses oxygen.

The oxidation value increases during oxidation; The oxidation value decreases when reduced. Oxidation, reduction both refer to reactants (molecules, ions, or atoms).

Oxidation is also known as oxidation reaction. When organic matter reacts, the effect of introducing organic matter into oxygen or removing hydrogen is called oxidation; The action of introducing hydrogen or losing oxygen is called reduction. The oxidation of a substance that reacts slowly with oxygen and slowly heats up without emitting light is called slow oxidation, such as metal rust, biological respiration, etc.

Intense luminous oxidation is called combustion.

Oxidation is a chemical reaction between a substance and oxygen, in which oxygen is provided. Examples:

1. Magnesium burns in oxygen: 2mg + o=2mgo White signal flare phenomenon: emits dazzling white light; Heat is released; A white powder is generated.

2. Iron burns in oxygen: 3Fe + 2O=FeO Phenomenon: Burning violently, sparks are everywhere; Heat is released; Generates a black solid (ferric tetroxide Feo) Note:

A small amount of water or fine sand should be placed at the bottom of the bottle to prevent the generated solid matter from splashing down and bursting the bottom of the bottle.

3. Copper is heated in the air: 2cu + o= =2cuo phenomenon: the copper wire turns black and is used to check whether it contains oxygen.

4. Aluminum combustion in the air: 4AL + 3O = 2alo phenomenon: emits dazzling white light, exothermic, and white solid is generated.

5. Combustion in the air in hydrogen: 2h + o=2ho High-energy fuel phenomenon: light blue flame is generated; Heat is released; Water mist appears on the inner wall of the beaker.