How to use the conservation of high school chemistry, and what are the conservation principles of hi

Whether it is the ionization of weak electrolytes or the hydrolysis of salts, their solutions are electrically neutral, i.e., the positive and negative charges are equal. Conservation of electric charge.

The hydrogen ions and hydroxide ions produced by the ionization of water are always equal, and the same is true for water in solution. Water is conserved in ionization.

The atoms or ions that make up the inside of a substance always have a fixed proportion. The so-called conservation of materials.

Take Na2S solution as an example to illustrate the equation relationship

Na2S is completely ionized with 2Na+ S2-

a 2a （a－b)

S2-H2O hydrolysis reversible Hs-OH-

b b （b－c） b

Hs-H2O hydrolysis reversible H2S OH-

c c c c

H2O ionization reversible H+ OH-

d d dc(na+) c(h+) 2 c(hs-) 2c(s2-) c(oh-) charge is conserved.

c(oh-) c(hs-) 2c(h2s) c(h+) ionization conservation.

C(Na+) 2 C(Hs-) C(S2-) C(H2S) Conservation of materials (Na is 2 times the total amount of S).

The amounts of a, b, c, and d are given above, which can be brought into verification.

Conservation of mass is mainly calculated to find the quantity of matter and the concentration of solution.

For other conservations, please refer to the 1st floor.

The law of conservation of mass.

The law of conservation of electron transfer.

The three major conservations are as follows:

The three major conservation values of high school chemistry are:

1. Conservation of electric charge.

That is, the solution is always electrically neutral, so the total positive charge of the cation band is the total negative charge of the anion band.

2. Conservation of materials.

That is, the specific proportional relationship between some elements present in the composition of the added solute, since there must be H and O elements of water in the aqueous solution, the equation in the conservation of materials must be the relationship of non-H and O elements.

3. Conservation of protons.

That is, the conservation of H+, the total loss of H+ in the solution is equal to the total number of H+, or the total amount of H+ ionized by water in the aqueous solution is always equal to the total amount of Oh- ionized by water.

Introduction:

Chemistry is a kind of natural science, mainly at the molecular and atomic levels, studying the composition, properties, structure and change laws of matter, and creating new substances (the essence is molecules that do not exist in nature). The world is made up of matter, and there are two main forms of change: chemical change and physical change (there are also nuclear reactions).

The four major conservation are: conservation of electrons, conservation of mass, conservation of protons, and conservation of materials.

Conservation of electrons means that in the redox reaction, the total number of electrons obtained by the oxidant is equal to the total number of electrons lost by the reducing agent.

The sum of the masses of the excavation ridges of the seepage substances participating in the chemical reaction is equal to the sum of the masses of the substances generated after the reaction.

Proton conservation means that the number of protons lost by the acid and the number of protons obtained by the base are the same.

Conservation of materials means that the original concentration of a component in a solution should be equal to the sum of its concentrations in various forms of existence in the solution.

There are three conservation laws in high school chemistry: conservation of protons, conservation of charge, and conservation of materials.

Proton conservation means that the number of protons lost by the acid is the same as the number of protons gained by the base.

Conservation of charge: 1. The algebraic sum of the positive and negative valency of the elements in the compound is zero.

2. The total number of positive charges carried by all cations in the solution is equal to the total number of negative charges carried by all anions.

Conservation of materials: 1. Conservation of particles containing specific elements.

2. The specific particles formed between different elements are conserved in the ratio of birot.

3. The relationship between specific particles is conserved.

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That is, the original concentration of a component in the solution should be equal to the sum of its concentrations in the various forms in which it exists in the solution. That is, the conservation of elements, the number of atoms of a certain element before and after the change is conserved. For example, in NaHCO3 solution, if HCO3- is not ionized and hydrolyzed, then the concentration of Na+ and HCO3- is equal.

Now HCO3- will be hydrolyzed into H2CO3, ionized as CO32- (both are 1:1 reactions, that is, the consumption of a HCO3-, will produce a H2CO3 or CO32-), then the concentration of Na+ and the concentration of HCO3- and its products are equated (or directly regarded as the conservation of sodium and carbon).

i.e. C(Na+) C(HCO3-) C(CO32-) C(H2CO3).

Another example: In the H2S solution, there is an ionization process as follows:

h2s=(h+) hs-)

hs-)=h+)+s2-)

h2o=(h+)+oh-)

The material conservation formula C(S2-)+C(Hs-)+C(H2S)==, (where the conservation of materials is the conservation of the S element - it is enough to describe the ions and molecules with the S element).

Another example: the charge is conserved, the material is conserved, and the proton is conserved in the Na2CO3 solution.

Sodium carbonate: conservation of electric charge.

c(na+)+c(h+)=2c(co32-)+c(hco3-)+c(oh-)

In the above equation, the total charge of anion and cation should be equal, since the charge of 1mol of carbonate is 2mol of negative charge, the amount of charge carried by carbonate is twice the amount of its substance.

Conservation of materials. C(Na+) is twice the amount of carbonate ionic substances, and after ionization and hydrolysis, carbonate exists in three forms.

c(na+)=2[c(co32-)+c(hco3-)+c(h2co3)]

Conservation of protons. C(H+)=C(oh-) ionized by water

The hydrogen ions ionized from water in the aqueous solution of sodium carbonate exist in three forms of (H+, HCO3-, H2CO3), in which 2mol of hydrogen ions ionized by water are in 1mol of carbonic acid molecule.

So C(OH-) = C(H+) + C(HCO3-) + 2C(H2CO3).