Please take the microscopic process of water electrolysis reaction as an example to illustrate the e

Electrolysis of water. Microscopic process: 2 water molecules.

It is decomposed into 2 oxygen atoms and 4 hydrogen atoms, 2 oxygen atoms are recombined into 1 oxygen molecule, and 4 hydrogen atoms are recombined into 2 hydrogen molecules. To put it simply, a molecule is broken down into atoms, which are then reassembled into new molecules.

Therefore, the essence of a chemical reaction is "the generation of new molecules in the process of change".

Expansion: 1. Molecular definition: A molecule is a substance that is a constituent substance and maintains the chemical properties of the substance.

A kind of particle.

Second, the characteristics of the molecule.

1.There are gaps between molecules. For example, take 50 ml of alcohol and 50 ml of water and mix them to a volume of less than 100 ml.

2.All the molecules that make up matter are in a never-ending irregular motion. The higher the temperature, the faster the molecular diffusion, and in solids, liquids, and gases, the gas diffusion is the fastest.

Since the motion of molecules is related to temperature, this motion is called the thermal motion of molecules. For example, clothes tend to dry in the sun when it's hot.

3.The order of magnitude of the diameter of a general molecule.

is 10 to the negative power m.

4.The molecule is small but has a certain volume and mass.

5.The molecular properties of the same substance are the same, and the molecular properties of different substances are different.

The electrolytic 2H2O=2H2+O2 chemical reaction is really the old bond breaking, and the new bond is established. The hydrogen-oxygen bond is broken, forming a new oxygen-oxygen and hydrogen-hydrogen bond. Follow-up:

Let's keep it simple. I'm in my third year of junior high school. I don't understand what :

It is to produce something new out of the old. The type and number of atoms have not changed. Beg.

1. The reaction essence of all electrolyzed water.

Under the action of direct current, the water molecule is destroyed and decomposed into the nucleus of hydrogen and oxygen atoms, two hydrogen atoms combine into one hydrogen molecule, and a large number of hydrogen molecules are condensed into hydrogen; Two oxygen atoms combine to form one oxygen molecule, and a large number of oxygen molecules condense into oxygen.

Hence water is made up of the elements hydrogen and oxygen. Furthermore, it is verified that in chemical changes, molecules can be redivided, but atoms cannot be redivided.

It is the movement of electrons, microscopically, H ions gain electrons at the positive electrode (not the positive and negative electrodes of the power supply) to become hydrogen, and O ions lose electrons at the negative electrode and combine to become oxygen; Macroscopic, positive and negative electrodes have bubbles.

From a microscopic point of view:

Under the action of electric field, hydrogen ions move to the negative electrode and get electrons at the negative electrode, become hydrogen atoms, and then combine with other hydrogen atoms to form hydrogen molecules.

The hydroxide ion moves to the positive electrode, and loses electrons at the positive electrode to become oxygen atoms and hydrogen ions, and the oxygen atoms combine with other oxygen atoms to form oxygen molecules.

Water is electrified to generate hydrogen and oxygen, oxygen is composed of oxygen elements, hydrogen is composed of hydrogen elements, indicating that water is composed of hydrogen and oxygen The chemical reaction formula of electrolysis of water is 2h

o Energized. 2h↑+o

So the answer is: 2h

o Energized. 2h↑+o

Hydrogen and oxygen are two elements

a. Electrolysis of water to produce hydrogen and oxygen, hydrogen is composed of hydrogen elements, and oxygen is composed of oxygen elements, the experiment proves that water is composed of hydrogen and oxygen elements, so the option is wrong

b. Electrolysis of water to generate hydrogen and oxygen, the reaction conforms to the characteristics of "one becomes many", which belongs to the decomposition reaction, so the option is correct

c. The test tube connected to the negative electrode generates hydrogen, which is flammable and can be burned, so the choice is wrong

d. When electrolyzing water, the volume of gas generated in the test tube connected to the positive electrode of the power supply is small, and the volume of gas in the test tube connected to the negative electrode of the power supply is more, and the volume ratio of the two is about 1:2, so the option is wrong

Therefore, b

Gas is produced on both poles, and the anode produces 1 2 times more gas than the cathode.

Principle: 2H2O = Electrolysis = 2H2 ( ) O2 ( ) Anode: 4OH - -4E- = 2H2O + O2 ( ) Cathode: 4H+

4e-=2h2（^）

The essence of the decomposition reaction of water: the electrolysis of water molecules into O and H atoms, and the recombination of O and H atoms to form new molecules O2 H2, that is, to form oxygen and hydrogen.

【Answer】c

Answer analysis] Test question analysis: a. Water is composed of hydrogen and oxygen, and the experimental conclusion is drawn through the experiment of electrolysis of water, so the choice is wrong

b. There is hydrogen and oxygen generated, which is an experimental conclusion obtained through the experiment of electrolysis of water, so the option is wrong

c. After power-on, there are bubbles on the electrode, and the ratio of the volume of gas in the two test tubes is about 2:1, which can be directly observed, so the option is correct

d. Each water molecule is composed of two hydrogen atoms and one oxygen atom, and the experimental conclusion is obtained through the experiment of electrolysis of water, so the choice is wrong

Therefore, choose C test center: electrolyzed water experiment

Comments: This question is not difficult, and you can correctly answer this question by mastering the experimental phenomenon of electrolyzed water; However, it is important to note the difference between experimental phenomena and experimental conclusions

Hello, landlord.

The formula that represents the ionization of the electrolyte is called the ionization equation, which is referred to as the ionization formula. Such as: MGCL

mg2clnaoh=na

When writing ionization equations, there are a few things to keep in mind:

1) The chemical formula is written on the left side of the formula, which indicates the state of the electrolyte when it is not yet ionized; On the right is written the ion symbol, which indicates the ions produced by the ionization of the electrolyte.

2) The number of charges carried by the ion should be equal to the valency number of the element or atomic cluster.

3) In the electrolyte solution, the total number of positive charges carried by the cations is equal to the total number of negative charges carried by the anions. Such as:

4) Writing ionization equations must be based on facts, not fabrications.

Ionization equation two.

The formula that represents the ionization of the electrolyte. For example, the ionization equations for aluminum sulfate and acetic acid are: CH, respectively

coohch

The chemical formula of the COOH electrolyte is written on the left, the ion symbol is written on the right, and the cation and anion are separated by a plus sign and connected by an equal or reversible sign in the middle. The total number of positive charges carried by the cations ionized by the electrolyte is equal to the total number of negative charges carried by the anions, and appropriate coefficients should be assigned to the cations and anions so that the total number of positive and negative charges of the ions is equal. For example, in the ionization equation for aluminum sulfate, the total number of sub-negatives is also 6.

The strong electrolyte is completely ionized in water, and the solution is not in ionization equilibrium, and its ionization process is indicated by an equal sign. Aluminum sulfate is a strong electrolyte, and its ionization equation is represented by an equal sign in the middle to indicate that aluminum sulfate is completely ionized. The weak electrolyte is partially ionized in water, and there is a reversible process of ionization and binding in the solution, and its ionization process is indicated by a reversible sign.

Acetic acid is a weak electrolyte, and its ionization equation is partially ionized with a reversible sign in the middle of the acetic acid. And the group.

Many complexes are soluble in water and ionized to form two ions, the inner field and the outer boundary. For example, the ionization equation for copper tetraaminophosphate ( ):

In water, a certain degree of ionization can also occur. The ionization equation for the copper tetraamino( ) ion: Cu(NH

cu4nh If you are satisfied, hope, thank you.

1) Water is formed by the H and O element bridges, and (2) water can be divided into H2 and O2 under certain conditions

The reaction of electrolytes in solution is essentially the reaction between ions, and such a reaction is called an ion reaction; Metathesis reaction, which is essentially the exchange of two electrolytes in a solution ion reaction, if it can combine with each other into what kind of substance, then metathesis reaction can occur, please give three examples of substances and express them by chemical equations:

Gases such as CO2 H2 NH3 precipitate such as BaSO4 AGCL CaCO3 Weak electrolytes such as H2O HAC HF equation Follow the above search for better or not.