High school chemistry reaction rate, good foundation, don t mislead teenagers

The only factors that affect the reaction rate are: concentration, pressure, temperature, catalyst. (Both forward and reverse reactions are affected).

The higher the concentration, the faster the reaction.

The higher the pressure, the faster the response.

The higher the temperature, the faster the reaction.

There is a catalyst, which reacts faster than no catalyst (usually a catalyst is a positive catalyst) and affects the chemical equilibrium with: concentration, temperature, and pressure.

According to Le Chatre's principle, the reaction proceeds in a tendency to weaken this reaction.

For example, the positive reaction is exothermic, and when you cool down, the temperature becomes lower, and the reaction will continue to increase the temperature.

For example, the gas coefficient on the left is large, and the gas coefficient on the right is small. When you pressurize, the pressure increases, so the gas decreases in volume to reduce the pressure, and the reaction should be strengthened towards the side with the smaller coefficient.

The above is a conceptual question that I typed by hand. Now back to your question.

The reason why point x reacts slower than point y is because point y has a strong pressure, and according to the theory above, the reaction rate of strong pressure is faster.

The X reaction is slower than the Y reaction, which refers to both the positive reaction and the reverse reaction.

In fact, when learning the content of reaction rate and equilibrium, we must pay attention to distinguishing the relationship between the influencing factors of rate and the influencing factors of equilibrium.

To put it simply, the rate must first affect the equilibrium, and the change in the rate does not necessarily affect the equilibrium (the forward and reverse reactions may change to the same degree).

Specifically, when the pressure increases, the reaction rate with the participation of gas (whether it is positive or negative, just depends on the presence or absence of gas) must increase (but the larger amount of gas will increase more obviously, so the equilibrium moves in the direction of decreasing gas volume).

The same is true for temperature changes.

1.Here the rate of reaction is the overall effect, i.e., the amount of change in reactants or products per unit time.

When measuring, you can't know exactly how much is the positive reaction and how much is the reverse reaction, you can only measure the total amount. So the reaction rate here is the total amount of change, both positive and negative).

2.It is not possible to judge the speed relationship between the two.

There is a certain relationship between the speed and the concentration, the larger the concentration of reactants, the easier it is to react, and the greater the reaction speed, but in this problem, it is not possible to judge the size of the reaction speed according to the relationship between the pressure, you can give an example, the pressure increases the reaction, and the equilibrium is not reached in the first two minutes, and it is easy to know that the reaction speed in the previous second is greater than the next second, but the pressure in the next second is stronger than the previous second. ）

No, from P2 P1 alone, we can only see that the positive reaction is proceeding towards the trend of increasing pressure, and it is not clear which X or Y is closer to the end point of the reaction, but it should be that the speed close to the end point of the reaction is slow.

It's okay to ask questions, and don't trust any answer lightly, unless it's standard.

The reaction is divided into positive reaction rate and reverse reaction rate, and the reaction rate is related to the concentration.

That's right. P1 P2 is equivalent to pressurization, the equilibrium is to move, and the reaction rate is also to increase, so the former is less than the latter.

The velocity is related to the concentration and temperature, and here it should be that the concentration has changed, and the forward and reverse rates of point y are greater than those of x.

The first set of experiments: Na2S2O3 and H2SO4, a total of 20ml of mixed solution, and the concentration after mixing is x 5ml 20ml=

Second set of experiments: The concentration after mixing is: x5ml 30ml=

The second group has a large concentration of reactants, so v2 >v1

The answer is d

This reaction is a single reversible reaction (only reactants are added), only the transformation of the reactants to be produced, the ratio of the reaction rate of the reactants is equal to the ratio of the number of measurements, and the rate of b multiplied by the time is the amount of b consumed.

The total amount minus the consumption is the amount of b remaining in the container.

(1) According to 2SO2 + O2 = 2SO3 (the middle is not an equal sign, it is a symbol of the reversible reaction), the SO2 = participating in the reaction, the generated SO3 = , and the SO3 concentration =.

2) SO2 average reaction rate = (.

3) According to the reaction equation, O2 = to participate in the reaction, then the conversion rate =

b Not necessarily, it is too broad to say from what situation the equilibrium will be reached.

According to the equation of thermal reaction, decreasing the temperature and increasing the pressure are the ways to make the equilibrium move forward, and the CD is half wrong.

So I can only choose B.

Since h<0 indicates that the reaction is exothermic, the forward reaction and the reverse reaction are accelerated at increasing temperature. A is wrong, the reflection is exothermic, so C is wrong, since the reaction is a reaction with a decrease in volume, the reaction with reduced pressure will move in the opposite direction of the reaction D wrong. So choose B.

The rate of a chemical reaction is a physical quantity used to express the decrease in the concentration of the product or the decrease in the concentration of the reactant per unit time.

Symbol: V, unit: mol (or mol (.)

Mathematical Expressions:

v = △c/△t

n/(v.△t)

Rule: In a chemical equation, the ratio of the chemical reaction rate of each substance is equal to the ratio of the stoichiometric number.

vw=vz=

So n = 1vy = the amount of y substance consumed at the end of 5 min is.

Percentage 25%.

The following are the difficulties and solutions to the difficulties.

First, it is necessary to understand the definition of enthalpy change entropy change.

Gaisce's Law (relatively simple, but its practicability cannot be ignored) Le Chattle's principle (the principle is simple, the application is more difficult, you must understand it deeply, do more questions about chemical equilibrium and explain it with Le Chattle's principle to achieve proficiency).

Collision theory (medium difficulty, not deep, but still familiar with its principle) Second, there must be a concept: ionization equilibrium, hydrolysis equilibrium, and dissolution equilibrium of refractory substances are all chemical equilibrium, but there are some characteristics. But it is necessary to grasp these characteristics and then solve them with the general method of solving chemical equilibrium.

3. The two units of chemical energy and electrical energy conversion and metal corrosion and protection must be proficient in all ionic reaction equations (do not be afraid to memorize ionic reaction equations).

The high school chemistry reaction rate section is not difficult. From the perspective of understanding, the calculation of the rate of chemical reaction and the relationship between the rate and the econometric coefficient of the chemical equation are difficult.