Higher than one into redox reaction and displacement reaction

The valency is changed before and after the displacement reaction.

Secondary school level. All the valencies of the displacement reactions change.

So. The displacement reaction is a redox reaction.

For example, common.

mg +H2SO4 == mgSO4 + H2 elemental magnesium changes from 0 valence to +2 valence.

The h element has changed from +1 valence to h2 (0 valence) I hope it will help you.

The valency before and after the displacement reaction [must change].

Elemental A + Compound B = Elemental C + Compound D

Element A changes from 0 valence to other valences, and element C changes from other valence states to 0 valences.

For example, zn + 2HCL == znCl2 + h2 zn changes from 0 to -2.

h changes from -1 to 0.

I hope mine is helpful to you, o(o!

Before and after the displacement reaction, the valency has changed: Zn + H2 SO4 = ZnSO4 + H2 (up arrow), Zinc has changed from 0 to +2.

The change in valency is the redox reaction.

So the displacement reaction must be a redox reaction.

If you don't understand, ask again.

The valence has changed before and after the displacement reaction.

The displacement reaction, which has a change in the valency of an element, a reaction in which an element gains and loses electrons, is a redox reaction.

Oxidation-reduction 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.

In the reaction, the substances that undergo oxidation reactions, called reducing agents, produce oxidation products; A substance that undergoes a reduction reaction, called an oxidant, produces a reduction product. Oxidation products are oxidizing but weaker than oxidants; The reducing product is reducing, but weaker than the reducing agent.

Common Oxidants:

1. Potassium permanganate (KMNO4).

Potassium permanganate has strong oxidation, and can oxidize alkyls, aldecordehydes, and aryl groups of primary alcohols, aldehydes, and aromatic ring side chains into acids.

2. Manganese dioxide (mnO2).

Manganese dioxide is a milder oxidizing agent that oxidizes methyl groups in the side chains of aromatic rings to aldehydes.

This question requires you to know that chlorine first reacts with iodine ions, then with ferrous ions after completion, and then with bromine ions after completion.

In the solution of 1 mol FEI2 and 2 mol Febr2, there are a total of 2mol iodide ions [1mol chlorine required], 3mol ferrous ions [chlorine required], and 4mol bromine ions [2mol chlorine required]; So by passing 2 mol Cl2, the ionic equation for the reaction is:

2cl2 + 2i- +2fe2+ =4cl- +i2 + 2fe3+

In the solution of 1 mol FEI2 and 2 mol Febr2, there are a total of 2mol iodide ions [1mol chlorine required], 3mol ferrous ions [chlorine required], and 4mol bromine ions [2mol chlorine required]; So by passing 3 mol Cl2, the ionic equation of the reaction is:

3cl2 + 2i- +3fe2+ +br- =6cl- +i2 + 3fe3+ +1/2br2

Removing the denominator will do the trick.

Oxidation: Br2>Fe3+> I2>Fe2+, so the reaction between Fe2 and bromine is to oxidize I- to I2 first, and then deoxidize Fe2+ if there is excess Br2. If Fe2+ is oxidized first, the Fe3+ generated will react with I- to form Fe2+ and I2.

It should be done in solution.

Copper chloride hydrolysis acidity: Cu2++2H2O=Cu(OH)2+2H+

Copper chloride hydrolysis acidity: Cu2++2H2O=Cu(OH)2+2H+

(3) Produced, then the amount of the transferred electron is 0 2___mol。

4) Clo2 has strong oxidizing properties. Therefore, it is often used as a disinfectant, and its disinfection efficiency (expressed in the number of electrons obtained per unit mass) is twice that of Cl2.

Analyze the first question.

According to the principle that the valency of the same element in the redox reaction can only be close to the middle, and there can be no crossing, therefore.

The +5 valent chlorine in potassium chlorate all becomes the +4 valent chlorine in chlorine dioxide to form a clo2

Two of the four HCl HCl are used as reducing agents, and the -1 valent chlorine becomes the 0 valent chlorine in chlorine gas to produce 1 Cl2. The other two are used as salt 2kcl.

So to get mol Cl2 only transfer electrons mol

The second question about disinfection is to reflect the ability of oxidants.

Molecular weight of ClO2 After sterilization, Cl in ClO2 of +4 becomes Cl- 1molClO2 and the number of transferred electrons is 5 mol=5Na

It is not the number of electrons transferred per unit mass N1 = 5Na

Cl2 molecular weight 71 After sterilization, Cl in 0valent Cl2 becomes Cl- 1molCl2 and the number of transferred electrons is 2Na mol

The number of electrons transferred per unit mass is n2 = 2na 71

Then, according to the meaning of the title, the disinfection efficiency is n1 n2 =

, the transfer electrons are, the HCl participating in the reaction is, the HCl used as a reducing agent is calculated as 1mol, and the Cl in ClO2 is +4, which is reduced to -1 to obtain 5 electrons; Cl in Cl2 is 0 and drops to -1 to get 2 electrons (5

Using the conservation of valence, 2 Cl+5, 4 Cl-1 is converted to 2 -1, 2Cl+4, 2Cl0 or so, there are 4 Cl valency changes, 2 from +5 to +4 to be oxidized, 2 from -1 to 0 to be reduced. Indicates that 2 electrons have been transferred. From the ratio of coefficients in the equation, it can be seen that Cl2 has electron transfer.