Chemical hydrolysis question, is hydrolysis a chemical reaction

l of NaOH solution containing NaOH is, according to:

2naoh + co2 = na2co3 + h2o，na2co3 + co2 + h2o = 2nahco3

It can be seen that Na2CO3 and NaHCO3 are generated.

Salt ionization: Na2CO3 = 2Na+ +CO32-, NaHCO3 = Na+ +HCO3-, followed by hydrolysis:

CO32- +H2O = HCO3- +OH- (reversible, to a lesser extent), HCO3- +H2O = H2CO3 + OH- (reversible, to a lesser extent). So, C(Na+)>C(HCO3-)>C(CO32-)>C(OH-)>C(H+). And according to the conservation of charge, it can be known:

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

The gas is in the form of HCO3 and the rest is in the form of carbonic acid, and the carbonic acid two-step ionization is very weak, so there is very little carbonate in the solution.

Salt hydrolysis is a chemical reaction. There are two more cases. The dihydrolysis reaction is a chemical reaction with a large degree of reversibility, and most of the dihydrolysis reactions can be carried out completely.

The ordinary salt hydrolysis is a reversible reaction, and the degree of reaction is very small, so do not think that the hydrolysate is the main substance in the system, and the main substance in the system is still the ion of salt.

1. The meaning of hydrolysis

Hydrolysis is a chemical unit process that uses water to break down substances to form new substances. It usually refers to the hydrolytic equilibrium of salts. The hydrolysis of salts refers to the process in which the weak base cations or acid ions in the salts combine with the hydrogen ions or hydroxide ions produced by water ionization to form weak electrolytes.

The hydrolysis reaction is a reaction in which the salt reacts with water in the solution to change the acidity of the solution, which needs to be carried out under certain temperature conditions.

2. Introduction

Water reacts with another compound, the compound is decomposed into two parts, hydrogen ions in the water are added to one part, and hydroxyl groups are added to the other part, so that two or more new compounds are obtained, and the reaction process that satisfies these conditions is called hydrolysis.

The most industrially used is the hydrolysis of organic matter, mainly to produce alcohols and phenols. The hydrolysis reaction is the reverse reaction of the neutralization or esterification reaction. The hydrolysis of most organic compounds is difficult to carry out smoothly with water alone.

Depending on the nature of the hydrolysate, the hydrolytic agent can be sodium hydroxide aqueous solution, dilute acid or concentrated acid, and sometimes potassium hydroxide, calcium hydroxide, sodium bisulfite, etc. This is called alkaline hydrolysis and acid hydrolysis. Hydrolysis can be carried out in batch or continuous mode, with the former usually taking place in a tower reactor and the latter using a kettle reactor.

Hydrolysis ion equation:

Cu(2+) 2H2O Cu(OH)2 + 2H(+)Cu(2+) hydrolysis to generate hydrogen ions, so Cu(NO3)2 solution is acidic HNO3 is a strong acid, and HNO3 molecules are completely ionized in water, so NO3(-) is not hydrolyzed. Correspondingly, ch3cooh is not completely ionized in water, ch3cooh ch3coo(-)h(+) so ch3coo(-) is to be hydrolyzed, ch3coo(-)h2o ch3cooh+oh(-).

The amount of Cu(OH)2 produced by hydrolysis is very small, and no precipitation is visible. To see the Cu(OH)2 pellet, NaOH should be added

1 Ionization refers to the ionization of strong electrolytes in water to become positive and negative ions.

Hydrolysis refers to the combination of weak bisate, weak acid and other ions ionized by water in water to form weak acid or precipitate.

2. The weak acid combines with the hydrogen ions ionized by water to form a weak acid (weak electrolyte), so that the number of hydroxide ions in the water is greater than the number of hydrogen ions, so the solution is alkaline, and others can also be similarly analyzed.

3. In general, strong acids and alkalis, most salts are strong electrolytes.

I don't know if you understand...

It's a bit confusing to talk to people.

Solution:1

al3+3h2o=al(oh)3↓+

3h+co32-

h+=hco3-

hco3-h+=h2o+co2↑

Because Al3+ binds to OH-and CO32- binds to H+, the equilibrium shifts in a positive direction and is eventually completely hydrolyzed.

2al3+3co32-

3h2o=2al(oh)3↓

3co2↑2.Increase the concentration of salt, the concentration increases, the equilibrium shifts to the right (equivalent to increasing the reactants) but the equilibrium movement of hydrolysis is weak after all, and it is an indisputable fact when the concentration increases, so the ratio of hydrolysis to the overall ratio is the degree of hydrolysis, which is naturally reduced Remember: no matter what kind of chemical equilibrium, when the external conditions change, absolutely, the equilibrium movement is relative to the addition of water, relative to the dilution of the original solution, for weak electrolytes, a large number of anions and cations that make up the salt, add water.

For the addition of water, it can be seen from its hydrolysis equation that water is also a reactant, and the reactant is increased, and the equilibrium is shifted to the right.

Here you have gone into a misunderstanding.

Degree of hydrolysis] refers to the proportion of hydrolyzed ions to total ions.

When we say "the thinner the more hydrolysis", it means that the proportion of hydrolyzed ions in the solution to the total number of ions increases, which shows that the hydrolytic equilibrium moves in reverse.

If the concentration of the solution is not very large, the total number of hydrolyzed ions of the solution will increase with the increase of concentration, but the proportion of the total number of ions will decrease.

If you still can't understand it, you can use the limit method.

There is an infinitely dilute FeCl3 solution, although the degree of hydrolysis is very large, but the solution can be considered neutral.

The other is a dilute solution of FeCl3, although the concentration is larger than the previous one, and the degree of hydrolysis is reduced, but due to the more hydrolyzed ions, the solution will still be weakly acidic.

Now look at the problem:

The concentration of FeCl3 increased by adding saturated solution dropwise to dilute FeCl3 solution, and although the degree of hydrolysis decreased, the number of hydrolyzed Fe3+ increased.

Then, the higher the concentration of FeCl3 solution, the more Fe3+ hydrolyzed, the more OH- is bound, and the more acidic the solution is.

But the smaller the degree of hydrolysis, the inhibition of hydrolysis.

I don't know where your answer came from.

The correct answer should be the same as yours: the CH3COO-NA+ ratio will be larger.

As previously analyzed, when sodium acetate is added, the concentration of the solution will increase and the degree of hydrolysis will decrease.

Suppose the concentration of the original solution is C1 and the degree of hydrolysis of CH3Coo- is A1, and the concentration of the new solution is C2 and the degree of hydrolysis of CH3Coo- is A2

There are a1 a2

Then, the amount of free CH3CoO- in the original solution is C1(1-A1), which accounts for 1-A1 of the total amount of CH3CoO-

The amount of free CH3CoO- in the new solution is C2(1-A2), which accounts for 1-A2 of the total CH3CoO-

Sodium acetate is a strong electrolyte and is completely ionized:

ch3coona == ch3coo- +na+

Then, the ratio of CH3COO- to Na+ in the original solution is: C1(1-A1) C1 = 1-A1

The ratio of CH3COO- to Na+ in the new solution is: C2(1-A2) C2 = 1-A2

by a1 a2

Available in: 1-a1 1-a2

Therefore, as the concentration of CH3CoONA increases, the CH3CoO-Na+ ratio increases.

You must first make it clear that the thinner the more hydrolysis means that the degree of hydrolysis increases, but the acidity increases, and the concentration of C(H+) increases.

From the Fe3+ hydrolysis equation, we can see Fe3+ +3H2O==Fe(OH)3+3H+

It can be seen that the addition of a reactant, water, can shift the equilibrium in a positive direction. That is, the degree of hydrolysis increases.

Although dilution will promote the hydrolysis of salts, due to the addition of a large amount of water, the concentration of each component in the solution is actually decreasing.

Sodium acetate solids are added to the sodium acetate solution, and the Na+ ionized by sodium acetate should be the same as CH3COO-, but due to the hydrolysis of CH3COO-, its concentration will decrease, but Na+ will not, so the CH3CoO-Na+ ratio will decrease.

When analyzing the problem, it is necessary to distinguish the priority clearly, the degree of hydrolysis is generally relatively weak, and the degree of influence is not as obvious as the direct change from the outside world.

The two are not contradictory, and the FeCl3 saturated solution is acidic. No matter how dilute unsaturated FeCl3 is, how much hydrolyzed acid performance is there? The saturation is very powerful as soon as it is slightly hydrolyzed, and the ch3coo-na+ is a 1:1 relationship.

I really feel a little speechless when I see this question, I'm afraid that the level of the person who makes this kind of question is not enough.

First of all, let me explain your question according to the intent of the questioner.

Fe3+ is hydrolyzed, Fe3+ +3H2O - reversible---Fe(OH)3 (for colloids can not be precipitated) +3H+

The F- of NAF in the solution has: F- +H2O -- ---reversible HF + OH-, which will be hydrolyzed to produce OH-, OH- will be combined with Fe3+ hydrolyzed H+, according to the principle of equilibrium reaction, the product reduction reaction will be carried out in the direction of increasing this substance, simply put, the hydrolysis of Fe3+ will intensify to increase H+ (the hydrolysis of F- will also be intensified), so Fe(Oh)3 will be produced in large quantities, because it is yellow, the color of the solution will be deepened, Because the H+ concentration of the original Fe3+ solution decreases, the pH value increases. This is also the knowledge of double hydrolysis.

But there is a very important issue that is overlooked here, F- can be combined with Fe3+ (commonly known as complexation) to form a colorless complex FeF3, which can be soluble in water, so if your book does not emphasize a small amount of NaF or its solution, then there will be a serious mistake, because the addition of a large amount of F- will make the solution lighter.

At room temperature, the Hna of a certain acid with pH = 2 was mixed with the same volume of a certain base B(OH) M with pH = 12.

Weak bases are not completely ionized, so there are bases that are not ionized, and when the reaction is completed, they will continue to ionize oh- and appear alkaline.

When the HA is mixed with the same concentration of NaOH in the same volume, pH = 8, HA is a weak acid, and the hydrolysis of NaA will produce OH-,

The hydrolysis of DNA2S consumes one H ion to generate one Hs ion, which promotes the ionization of water and makes it in solution.

Charged particles. The number increases, while.

H2SO4 and.

nahso4

Ionization produces H ions, which inhibits water ionization and makes the water charged.

Ion concentration and transport socks.

decreased, and H2SO4 was more aggressive than NaHSO4 on the inhibition of quiet water. So choose D