High two chemical equilibrium conversion rate problem for detailed answers

Conversion rate = change (consumption) Initial amount.

1.When A=B+C, the introduction of A is equivalent to increasing the pressure of the system, because this is a reaction with the same volume of gas, the increased pressure equilibrium will not move, so the conversion rate of A does not change.

2.When A>B+C, the introduction of A is equivalent to increasing the pressure of the system, because this is a reaction of reducing the volume of the gas, the increased pressure equilibrium will move in the positive direction, so the conversion rate of A increases.

Your last question: for example.

2no2（g）*****n2o4（g）

Increase the pressure. The balance moves towards volume reduction. Even if it moves in the forward direction. Then no2 will be consumed. Therefore, the amount of change (consumption) increases. Conversion rates increase.

1 Because the volume difference is zero, there is only one reactant, and the concentration of A is increased, although there are more products B and C, but the concentration ratio of A is increased.

The balance does not move, so the conversion rate of a does not change 2 The same balance shifts to the right 3 There is a relationship, and it depends on the relationship of concentration, and it does not necessarily increase.

1 is the equivalent equilibrium, which is only related to temperature, and has nothing to do with concentration and pressure. Only increase A, the effect is the same as the same proportion of increasing BC, but the pressure is changed, so the conversion rate of A is unchanged 2 is the reaction of volume reduction, increasing the concentration is equivalent to decreasing the volume, and the reaction is naturally carried out in the direction of volume reduction, so the conversion rate of A is increased The equilibrium has nothing to do with the conversion rate, only with temperature. Where the equilibrium is shifted without adding reactants, the conversion rate of ** increases.

Formula:Conversion rate for agingReactant change Reactant initiation x 100%.

Differences:

The equilibrium conversion rate is the conversion rate of the reactants when the reaction reaches equilibrium.

The conversion rate is the ratio of the amount of change in reactants to the amount of input at any given time.

If the amount of reactants A and B is increased by the same multiple of the original proportion, the equilibrium shifts to the direction of the positive reaction, and the conversion rate of the reactants is related to the stoichiometric number.

For example, A+B=C+D, the conversion rate of AB remains unchanged. (The same is true for the principle of compression) quietly rises.

Such as A+B equivalence equilibrium.

For example, A+B>C+D, the conversion rate of AB increases. (Explained by the principle of compression, the equilibrium and the original equilibrium are no longer equilibrium.) ）

The former is a variable Si Yuanla, and the latter is a constant quantity, in the chemical cavity hand balance, the conversion rate = C to C * 100%.

or =n to n to start * 100% such as.

N2(g)+3H2(G)==2NH3(G)C.

0c change. End. Conversion rate (n2) = c change (n2) c start (n2) * 100%.

The equilibrium conversion rate is the conversion rate of the reactants when the reaction reaches equilibrium.

The conversion rate is the ratio of the amount of change in reactants to the starting amount at any given time. Na line.

Formula: Conversion rate Change of reactants of tomato Reactant Initial amount of reactant x 100%.

Effect of concentration on conversion rate: Under the condition that other conditions remain unchanged, the conversion rate of reactants may increase, or may decrease or remain unchanged when changing the concentration.

a. Reduce the concentration of the product, and the conversion rate of the reactant must increase;

bFor the reaction in which a variety of substances participate, increasing the concentration of a certain reactant will increase the conversion rate of other reactants, and the conversion rate of the reactant itself will generally decrease;

cFor the decomposition reaction, the conversion rate depends on the number of substances before and after the reaction. If the total amount of the gas cushion before and after the reaction is equal, such as 2Hi (g) H2 (g) + I2 (g), no matter how the concentration of the reactant is changed, the conversion crack rate of the reactant remains unchanged; If the number of molecules decreases after the reaction, such as 2NO2<==N2O4, and the concentration of reactants is increased, the conversion rate of reactants increases. If the number of gas molecules increases after the reaction, such as 2NH3<==N2+3H2, the concentration of reactants increases, and the conversion rate of reactants decreases.

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Problem description: Why for the reaction ma (gas) + nb (gas) Analysis: Assuming that A and B each have a return to 1mol, then after a period of reaction, the amount of both substances decreases, and then 1mol B is added, then the A participating in the reaction is less than 1mol, so the B added later cannot reach the first conversion amount, and the conversion rate is not reduced; And A responds partially, and the conversion rate increases.

It is equivalent to a small amount of A pinning down B's reaction.

If there is only one reactant, there is no pull-in effect. Then the conversion rate of the gas depends on the change in pressure.

For example, 2Hi = H2 + I2, the pressure before and after the reaction is unchanged, and then Hi is added, and the balance does not move, the conversion rate remains unchanged;

PCL5=PCL3+CL2, after the reaction, the pressure becomes larger, then the gas increases and the equilibrium moves in the opposite direction, and then Pcl5 is added, and the conversion rate decreases.

2NO2 N2O4, the pressure becomes smaller after the reaction, the gas increases and the equilibrium moves forward, and NO2 is added, and the conversion rate increases.

The relationship between the direction of chemical equilibrium movement and the conversion rate of reactants is:

1. If the temperature is changed, if the equilibrium shifts to the direction of the positive rapid hunger reaction, the conversion rate of the reactants must increase. On the contrary, if the equilibrium shifts to the opposite reaction direction, the conversion rate of the reactants must be reduced.

2. Change the pressure, if the equilibrium moves to the direction of positive reaction, the conversion rate of reactants must increase. On the contrary, if the equilibrium shifts in the direction of the opposite reaction, the conversion rate of the reactants must be reduced.

The reaction equilibrium of a gas depends on the (gas) volume of reactants and products.

1. The volume of the reactant is 2, the volume of the product is "2+1", that is, 3, the volume of the product is greater than the volume of the reactant, so when the reaction is balanced, the addition of gas will promote the reverse reaction, thereby reducing the conversion rate (your question must be "I added the reactant, how to reduce it", remember, it is the conversion rate rather than the conversion amount, and the addition of reactants must increase the reaction amount and the reaction rate is not necessarily);

In the same way, it is still a problem of conversion rate, increasing SO2 will provide O2 with more opportunities to contact SO2 (to put it more deeply, it is called a relative increase in reaction area), and the conversion rate of O2 will increase. What about SO2: to explain by the reaction rate formula, the amount added to the denominator increases, while the amount of reaction in the molecule increases because there is not enough O2 to react with it (i.e., the reaction area is relatively reduced).

2. This is a common problem, the test point is that N2O4 is solid, so the reaction equilibrium no longer looks at the "volume" of reactants and products (referring to the volume of gas), so no matter which reactant on both sides of the increase = on both sides, the corresponding product will increase.

3. Here Hi and H2 are both gases, and I2 is solid, so the volume of gas before and after the reaction remains unchanged, increasing H2, the relative reaction area of H2 increases, so the conversion rate increases, and the relative reaction area of H2 decreases, so the conversion rate decreases (the same as 1); Because there is no change in the volume of the gas before and after the reaction, the conversion rate remains the same, while the conversion amount of Hi must increase.

In short, we must distinguish the relationship between conversion volume and conversion rate in our consciousness.

If you still have any questions, you can add them.

(1).Constant volume, adding SO3 is equivalent to pressurization. The reversible reaction proceeds in the direction of a decrease in the number of gas molecules. So the SO3 conversion rate decreases.

If the concentration of SO2 increases, the effective collision between O2 and SO2 increases, and the conversion rate of O2 increases. The SO2 and O2 reactions are reversible, and the increased SO2 cannot reach the previous conversion rate. **Turnover rate = total reactants of the reaction).

2) The volume remains unchanged, that is, the volume is fixed. Increasing the NO2 concentration is equivalent to pressurization, and the reversible reaction proceeds in the direction of decreasing the number of gas molecules. As mentioned above, the increased reactants cannot reach the previous reaction rate, but the attraction effect of pressure is great, so the conversion rate of total NO2 becomes larger.

Increasing the concentration of N2O4 is also equivalent to pressurization. The reversible reaction also proceeds in the direction of a decrease in the number of molecules of the gas. So the NO2 conversion rate becomes larger.

3), Ibid. (1), the second question. The increase in Hi conversion rate does not change, because it is a reaction with the same number of gas molecules. So increasing hi has no effect on reaction speed.

That's all I can say, I hope it can be understood and helpful to you.

1 Because this reaction is a reaction in which the gas participates, your reaction volume is 2 volumes, and after the reaction is 3 volumes, when you increase the concentration of sulfur trioxide, it is equivalent to the pressure of your reaction system increases, and when the pressure increases, the reaction proceeds in the direction of decreasing pressure, so for reversible reactions, the conversion rate of sulfur dioxide decreases.

2 Because they are all gases, when the concentration of reactants increases, the concentration of the system increases, and the reaction proceeds in the direction of volume reduction, so the concentration of nitrogen dioxide increases, the conversion rate of nitrogen dioxide increases, and vice versa.

3 This reaction is a reaction with constant volume.

When the concentration of hydrogen increases, it means that there is an excess of hydrogen, so the conversion rate of iodine vapor increases, and the concentration of hydrogen iodide increases, which is equivalent to the reaction volume of the whole system does not change, so the conversion rate does not change.

The process of increasing the concentration is equivalent to increasing the pressure in the direction of the reaction, and the direction of the reaction is judged according to the direction of the change in pressure.

This kind of problem is mainly considered from the volume change, and if you understand this knowledge point thoroughly, you can basically get points for this piece of knowledge.

1. For the reversible reaction of reactants with a variety of substances, the conversion rate of this substance will decrease if one substance is added. This is because, the conversion rate = the amount of the transformed substance The total amount of the substance, now this substance is added, so the amount of the transformed substance increases, but the total amount of the substance increases more, so the ratio decreases, that is, the conversion rate decreases (this is only qualitative analysis, it is difficult to quantitatively analyze).

Increasing the SO2 concentration reduces the SO2 conversion rate (analyzed above); The increase in the conversion rate of O2 is due to the fact that after the addition of SO2, the equilibrium shifts in a positive direction, so the amount of substances converted by O2 increases, while the total amount of substances in O2 remains unchanged, so the conversion rate increases.

22NO2(G) = reversible = N2O4

This reaction is special because there is only one reactant, which does not satisfy the situation mentioned in question 1. A different method of analysis is to be employed. (Set Intermediate Method).

To increase the concentration of NO2, we can first set the intermediate state, that is, perform an isobaric transformation (increase in the volume of the container), so that the conversion rate of NO2 does not change (the conversion rate of isobaric change does not change), and then reduce the volume of the container, for this reaction, decreasing the volume of the container will make the equilibrium move in a positive direction, so NO2 will continue to convert to N2O4, so the conversion rate of NO2 increases.

The same is true for increasing the concentration of N2O4 and increasing the conversion rate of No2.

3 This reaction is a special case of problem 2 (the most special case of a reversible reaction, there is only one reactant, and the volume of gas before and after the reaction is unchanged).

It is still possible to use the intermediate state method, but the volume of the intermediate container is the same as the volume of the final container, so the conversion rate remains the same.

If you still have any questions, you can hi me.

First of all, let's talk about the calculation method of conversion rate: (the conversion concentration of a reaction The initial concentration of the substance) * 100%.

Secondly, for a general reversible reaction (i.e., a reaction with more than two reactants), if the concentration of one reactant is increased, the transformation concentration of the other reactant must increase, but the initial concentration does not change, so the conversion rate of the other reactant must increase. However, for the reactant with increased concentration, although the conversion concentration increased, its initial concentration also increased (and the increase was larger than the former), so the conversion rate of the reactant decreased.

Third, for the 2NO2===N2O4 (reversible) reaction, this is a very special reaction, there is only one reactant and product, in this case, increasing the concentration of NO2, if the conversion rate before addition is still pressed, but the total amount of gas increases, it is equivalent to increasing the gas pressure in the reaction vessel, and increasing the pressure, the equilibrium will move in the direction of the positive reaction. Therefore, the NO2 conversion rate should be increased.

The explanation is as follows:

According to the principle of equilibrium movement, if one of the conditions affecting the equilibrium (such as concentration, pressure, or temperature) is changed, the equilibrium moves in a direction that can reduce the change.

This reaction is a gaseous reaction, increasing the amount of a, so that the pressure increases, then, the equilibrium should move in the direction of decreasing the pressure.

For (1), a b c, the pressure has no effect on this reaction, the equilibrium does not move, so the conversion rate of a does not change;

For (2), a b c, the equilibrium is shifted to the right, which can reduce the number of molecules of the gas in the container, reduce the pressure, and increase the conversion rate of a;

For (3),

a b c, the equilibrium moves to the left, which can reduce the number of molecules of the gas in the container, so that the pressure is reduced, and the conversion rate of a is reduced.