The concept of redox reaction, the concept of redox reaction

A redox reaction is a chemical reaction in which the valency of an element changes before and after the reaction. This reaction can be understood as consisting of two halves, namely oxidation and reduction.

Law. None of the metathesis reactions are redox reactions.

Displacement reactions are all redox reactions.

Most of the chemical reactions with the participation of elemental elements are redox reactions (with the exception of graphite turning into diamond under certain conditions, and also includes the conversion between other allotropes). ）

Most of the decomposition reactions with elemental formation are redox reactions (with the exception of hypofluoric acid decomposition: 2HF==2HF+O2, and the valency does not change).

The centering reaction, the disproportionation reaction can be regarded as a special redox reaction.

Conception. The essence of the reaction is that there is a change in valency, that is, there is a shift and shift in electrons. The half-reaction in which the sum valence increases, that is, the electron loss is an oxidation reaction; The oxidation number decreases, and the reaction to obtain electrons is a reduction reaction.

Substances with increased valence reduce each other and are oxidized by themselves, so they are called reducing agents, and their products are called oxidation products; Substances with reduced valency oxidize each other and are reduced themselves, so they are called oxidants, and their products are called reducing products. Namely:

Reducing agent + oxidizing agent – oxidation product + reducing product.

Generally speaking, the reducing product in the same reaction is weaker than the reducing agent, and the oxidation of the oxidation product is weaker than the oxidant, which is the so-called "strong reducing agent to weak reducing agent, strong oxidant to weak oxidant".

Summary: The oxidant undergoes a reduction reaction, electrons are obtained, the valency is reduced, it is oxidized, it is reduced, and the reduction product is generated.

The reducing agent undergoes an oxidation reaction, loses electrons, increases the valency, has reducibility, is oxidized, and generates oxidation products.

Notation: Redox is inseparable, and the gain and loss of electrons is fundamental. Those who lose electrons are oxidized, and those who gain electrons are reduced.

Reducing agent for those who lose electrons, oxidizing agent for those who gain electrons. Oxidant Reducing agent, interdependent and inseparable.

Notation 2: High oxygen loss, low return.

Explanation:1The valency increases, electrons are lost, and the oxidation reaction.

2.The valency decreases, electrons are obtained, and the reaction is reduced.

Notation 3: Liters and losses are returned by oxygen.

It was lowered and oxygenated.

Explanation:1The valency increases, electrons are lost, and they are oxidized as reducing agents.

2.The valency decreases, electrons are obtained, and they are reduced to oxidants.

There are many, as long as the valency of the elements involved in the reaction changes, it is a redox reaction.

For example, hydrogen and oxygen react to form water, hydrogen atoms lose one electron and are oxidized, oxygen atoms get two electrons, they are reduced, hydrogen is a reducing agent, and oxygen is an oxidizing agent, and the substances containing reducing substances in the produce are oxidation products, and those containing oxides are called reduction products, such as water is both an oxidation product and a reduction product.

Redox reaction is one of the three basic reactions in organic chemistry, and its essence is the gain and loss of electronic devices or the shift of shared electron pairs.

Redox reaction is a type of reaction in which the oxidation number of an element changes before and after a chemical change. The essence of redox reflection is the gain and loss of electronic devices or the deviation of shared electron pairs. Photosynthesis, plant photosynthesis, the production of chemical batteries for daily life, the metallurgical industry, and the launch of rockets are all closely related to redox reactions.

Scientific research on redox reflection is of vital practical significance to people's development.

1. Oxidation reaction and redox reaction have different oxygen requirements.

2. The oxidation value of oxidation reaction and redox reaction are different.

3. The efficacy of chemical substances that lose electrons is called redox reaction; The efficacy of electronic devices is called restoration.

At the end of the 18th century, chemists summarized the reactions of many substances with oxygen, found that such reactions had some similar characteristics, and put forward the concept of redox reactions: reactions with oxidation are called oxidation reactions; The reaction of taking oxygen from an oxygenated compound is called a reduction reaction. With the development of chemistry, it has been found that many reactions have similar characteristics to redox reactions in the classical definition, and after the development of the concept of valency in the 19th century, a class of reactions with increased valency was incorporated into oxidation reactions, and a class of reactions with reduced valency was incorporated into reduction reactions.

At the beginning of the 20th century, the electron theory of bonding was established, so the half-reaction of losing electrons was called oxidation reaction, and the half-reaction of gaining electrons was called reduction reaction.

Not only can the redox reaction be without oxygen, but even combustion can be done without oxygen!

In the junior high school stage, the redox reaction was analyzed from the perspective of oxygen gain and loss.

1. The reaction to obtain oxygen is an oxidation reaction; The reaction in which oxygen is lost is a reduction reaction.

2. The oxidation reaction and the reduction reaction occur at the same time and exist in the same redox reaction.

In the high school stage, the characteristics of redox reaction 1 and redox reaction were analyzed from the perspective of valency rise and fall: the valency of elements changed before and after the reaction.

2. The oxidation reaction shows an increase in the valency of the oxidized elements; The reduction reaction is characterized by a decrease in the valency of the reduced element.

3. The reducing agent is a substance with an increased valency of elements in the reaction; Oxidants are substances in which the valency of elements in a reaction decreases.

Redox reaction refers to the transfer of electrons in a substance during a chemical reaction. In this reaction, one substance loses electrons and is oxidized, and the other substance gains electrons and is reduced. Redox reaction is one of the most common types of chemical reactions and one of the important chemical reactions in life activities.

In redox reactions, oxidants refer to substances that are able to accept electrons from the blue hood, while reducing agents are substances that are capable of donating electrons. When the oxidizing agent and the reducing agent react, the electrons are transferred from the reducing agent to the oxidizing agent, so that the reducing agent is oxidized and the oxidant is reduced.

Redox reactions play an important role in life activities. For example, respiration in cells is a redox reaction that produces energy and water by reacting organic matter with oxygen. In addition, the enzymes in many organisms are also oxidizing progenases, which can promote redox reactions.

In conclusion, redox reaction is an important chemical reaction and plays an important role in life activities. They are able to facilitate the transfer of electrons between substances, resulting in energy and chemical changes.

Redox reaction refers to a chemical reaction in which the oxidation number of an element rises and falls accordingly before and after the reaction.

Redox reaction is an important reaction in chemical reactions. Combustion, respiration, photosynthesis in nature, chemical batteries, metal smelting, rocket launches, etc. in production and life are all closely related to this reaction.

Before and after the redox reaction, the oxidation number of the element changes. Depending on the increase or decrease in the oxidation number, the redox reaction can be split into two half reactions: the half reaction with the increased oxidation number is called the oxidation reaction; The reaction with a decrease in oxidation number is called a reduction reaction.

Oxidation and reduction reactions are interdependent and cannot exist independently, and together they constitute redox reactions.

The oxidation reaction loses electrons and is oxidized and the valency increases.

The reduction reaction yields that the electrons are reduced by the reduced valency.

1.The concept of redox reaction: Any chemical reaction with the valence of elements rising and falling is a redox reaction.

2.Characteristic: (Discriminant method) Valency changes.

3.Essence: There is electron gain and loss (or offset) in the reaction process4

Oxidation vs. Reduction Oxidation: A change in the loss of electrons (increased valency). Restore:

The change in electrons (reduced valency) is obtained.

Redox reaction is a type of reaction in which the oxidation number of an element changes before and after a chemical reaction. The essence of a redox reaction is the gain or loss of electrons or the shift of shared electron pairs. Redox reactions can be divided into two types according to the element that acts as an oxidizing agent and the element that acts as a reducing agent:

Intermolecular redox reactions, intramolecular redox reactions.

Whether a chemical reaction is a redox reaction can be judged according to whether the reaction has an increase in oxidation number, or whether there is electron gain, loss and transfer. If there is a conflict between the two, the former prevails, e.g. reaction 3O2 = 2O3, although the reaction has an electron pair shift, but since the IUPAC regulations have an elemental oxidation number of 0, this reaction is not a redox reaction.

The determination of redox reactions in organic chemistry is usually based on whether the oxidation number of carbon changes: if the oxidation number of carbon increases, the reaction is an oxidation reaction; When the oxidation number of carbon decreases, this reaction is a reduction reaction. Since in the vast majority of organic matter, hydrogen always presents a positive valence state, and oxygen always presents a negative valence state, so the reaction of organic matter to obtain hydrogen and lose oxygen is generally called reduction reaction, and the reaction of oxygen loss and hydrogen loss is called oxidation reaction.