What does a spontaneous redox reaction mean

The third floor is quite right, this is the knowledge of the university, the occurrence of any reaction, the essence of which is to judge whether the Gibbs function variable g is greater than zero: greater than zero, the reaction cannot be carried out spontaneously, less than zero, the reaction can be carried out spontaneously.

To correct this, the judgment g is applicable to all reactions. In the case of the redox reaction that occurs spontaneously, the criterion generally used is to judge the electrode potential difference of the reaction e, e>0, the reaction proceeds spontaneously, and e<0, which cannot be spontaneously. where there is a relation, g=-zfe;

In addition, there are also reaction quotient criteria related to judging whether the reaction can proceed spontaneously, and all of the above are the issues discussed in chemical thermodynamics and partial redox reactions. Hope you are satisfied.

A redox reaction is a reaction with valency transformation, the essence of which is the gain, loss or shift of electrons. The reaction that must occur spontaneously is the reaction of heat release and entropy increase, and the reaction of endothermy and entropy decrease must not occur spontaneously. The reaction with decreasing exothermic entropy and increasing endothermic entropy need to occur at a certain temperature, and the formula is g= h-t s, where h is the enthalpy variable, s is the entropy variable, and t is the open temperature.

For example, Zn reacts with dilute hydrochloric acid, while Cu reacts with dilute hydrochloric acid not.

It's literal, and it doesn't need to be conditional, and the system itself can happen.

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

That is, it does not need any conditions to happen, one side gains electrons, which is a reduction reaction, and one side loses electrons, which is an oxidation reaction.

A spontaneous redox reaction is a reaction in which a redox reaction can occur without the need for continuous external conditions. The essence of redox reaction is the gain and loss of electrons or the offset of shared electron pairs, and redox reaction is one of the three basic reactions in chemical reactions.

In nature, combustion, respiration, photosynthesis, chemical batteries in production and life, smelting of the genus of golden wheels, rocket launches, etc. are all closely related to redox reactions. The study of redox reactions is of great significance to the progress of mankind. The conditions under which the redox reaction occurs, from a thermodynamic point of view, are that the free energy of the reaction is less than zero; From an electrochemical point of view, the electromotive force of the galvanic cell is greater than zero.

In redox reactions, oxidation and reduction must be carried out simultaneously in equal amounts. The two can be likened to the relationship between yin and yang that is interdependent, transformed, ebb and flow, and oppositional to each other. Redox reactions are also present in organic chemistry.

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

All such reactions observe conservation of charge.

The Law of Strength and Weakness:Oxidation: oxidant oxidation product; Reducibility: Reducing agent" reducing product.

Valence Law:The element is in the most advanced state and only has oxidizing properties; The element is in the lowest valence state and is only reductive; It is in the intermediate valence state, which is both oxidizing and reducing.

The Law of Transformation:When the centering reaction occurs between different valence states of the same element, the oxidation number of the element is only close but not crossed, and the maximum value of the element reaches the same valence state.

Law of Precedence:For the same oxidant, when there are multiple reducing agents, it usually reacts with the most reducing agent first.

Law of Conservation:The number of electrons gained by the oxidizing agent is equal to the number of electrons lost by the reducing agent.

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".

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.

1 Conservation law: In a redox reaction, the total number of valency increases is equal to the total number of decreases, which is essentially the total number of electrons lost in the reaction and the total number of electrons gained. That is, n (oxidant) the number of valence atoms valency change value n (reducing agent) valence group number of valence atoms valency change value.

Application of the Conservation Law:

The quantitative relationship between the substances involved in the redox reaction is directly calculated.

Trim redox reaction equation.

2 Comparison of the strength and weakness of oxidation and reduction of substances and their applications:

Oxidation: Oxidant "Oxidation Product" "Reducing Product" Reducing Agent;

Reducibility: Reducing agent, "Reducing product", "Oxidation product", "Reducing agent".

The use of the law can be used to:

Determine the relative strength of oxidation mode or deficiency and reduction in a redox reaction.

Determine whether a redox reaction can be carried out normally.

First, the law of "two strong and two weak":

1.Determine the relative strength of the oxidation and reduction properties of particles.

2.Determine whether the redox reaction can occur.

Second, the law of "high oxygen, low return, and medium concurrent".

For atoms with different valence states of the same element, the most ** state is only oxidizing, the lowest valence state is only reducing, and the intermediate valence state is both oxidizing and reducing.

3. The law of "single strong from weak, single weak from strong".

1. The stronger the reducibility of the metal element, the weaker the oxidation of the corresponding cation; On the contrary, the weaker the reduction of metal elements, the stronger the oxidation of the corresponding cations.

Fourth, the law of "valence returns to the center and does not cross each other".

"Valence state centering" refers to the redox reaction between atoms of different valence states of the same element, and the intermediate valence state is always formed after the reaction between the ** state and the valence state.

Fifth, the law of "strong is easy to be weak and difficult, first strong and then weak".

"Strong and weak and difficult" means: the same oxidant (or reducing agent) reacts with different reducing agents (or oxidants) at the same time, and when the concentration of the reducing agent (or oxidant) is not much different, it is always reduced first.

6. The law of "conservation of quality and electricity".

Quality: Conservation of mass. Electricity: The number of electron transfers is conserved. That is, the total number of electrons obtained by the oxidant The total number of electrons lost by the reducing agent. This is the basis for the equation of the trim redox reaction, and it is also the basis for the calculation of the redox reaction.

It refers to a reaction that does not require external continuous conditions (such as continuous temperature changes) to undergo a redox reaction, which is called a spontaneous redox reaction, such as a galvanic battery.

Redox reactions are chemical reactions.

Before and after, there is a class of reactions in which the oxidation number of the element changes. The essence of a redox reaction is the gain or loss of electrons or the shift of shared electron pairs. Redox reaction is one of the three basic reactions in chemical reactions, combustion and respiration in nature.

Photosynthesis, chemical batteries in production and life, metal smelting, rocket launches, etc. are all closely related to redox reactions. The study of redox reactions is of great significance to the progress of mankind. 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 oxidation number increases, which is called the oxidation reaction.

The reaction with a decrease in oxidation number is called a reduction reaction.

According to the standard thermodynamic explanation, g (Gibbs free energy) is less than zero, and then there is g = -nfe, where e is the electromotive force of the galvanic cell·· It's good to replace it if e is greater than 0...

The general understanding is; It refers to the ability to react without the help of external conditions.

It is a redox reaction that does not need to be carried out according to the change of external environmental factors.

Yes! This one is thermodynamic.

Elective 4 "Principles of Chemical Reactions" in the chemistry textbook of the People's Education Edition

There is a formula for the heat of reaction block that is used to determine whether a reaction can proceed spontaneously

g (Gibbs free energy) = h (enthalpy change) - t (thermodynamic temperature absolute temperature) g (entropy change).

The fourth quadrant is green and proceeds spontaneously at any temperature The second quadrant is red and the positive reaction is non-spontaneous at any temperature The first quadrant is high temperature and low temperature is non-spontaneous The third quadrant is the opposite of the above.

The kind of reaction in the fourth quadrant is spontaneous, and if it is still a redox reaction, it is a redox reaction that can be carried out spontaneously.

In layman's terms, it is a reaction that can occur without external continuous conditions (such as continuous heating, ignition is not counted, ignition time is short, and there is no continuous ignition) is called spontaneous redox reaction.