Reaction limits in Chemistry Compulsory II and questions about calculations Please give it accuratel

First of all, it is necessary to understand that the so-called equilibrium state of chemical reaction is a state in which the concentration of reactants and products no longer changes with time when the rates of the forward and reverse reactions are equal in a reversible reaction system.

The state of chemical equilibrium has the characteristics of inverse, equal, dynamic, definite, and variable.

Inverse: The object of chemical equilibrium study is reversible reactions.

Equal: At equilibrium, the rate of forward and reverse reactions is equal, i.e., v positive = v inverse.

Dynamic: When equilibrium, the reaction is still ongoing, it is dynamic equilibrium, and the reaction is carried out to the maximum.

Constant: When the equilibrium state is reached, the concentration of each component in the reaction mixture remains unchanged, the reaction rate remains unchanged, the conversion rate of reactants remains unchanged, and the content of each component remains unchanged.

For the reaction Ma(G)+NB(G)PC(G)+QD(G):

1. If (a positive) = (a inverse) there is a certain equilibrium.

2. If the content, conversion rate, etc., these quantities no longer change, a certain equilibrium 3. In the adiabatic system, the temperature does not change a certain equilibrium.

4. Under constant temperature and constant capacity, the pressure remains unchanged if m+n=p+q, it is not necessarily balanced, if m+n≠p+q, it must be balanced.

5. If the substances in the system are not all gases, under constant capacitance, the density ( ) does not change and there is a certain equilibrium 6. The average relative mass of gas molecules does not change If m+n≠p+q is in a certain equilibrium, if m+n=p+q, it is not necessarily equilibrium.

If the substance is not all gases, the average relative mass is not necessarily unbalanced.

7. Sufficient conditions The quantity, mass, and concentration of the substance are unchanged and there is a certain equilibrium 8. If the color of the system is unchanged, there is a certain equilibrium.

This should not be used to determine whether the equilibrium is moving or not, because when the coefficient is unchanged before and after the reaction, changing the pressure will cause the color of the system to change, but the equilibrium will not move).

Characteristics of chemical equilibrium state: inverse, equal, dynamic, fixed, and variable.

Inverse: The object of chemical equilibrium study is reversible reactions, etc.: at equilibrium, v positive v inversion is greater than 0 (essential) dynamic:

In equilibrium, the reaction is still continuous, and it is a dynamic equilibrium Constant: In equilibrium, the concentration of each component of the reaction mixture is kept constant, and the percentage content is maintained at a certain level (appearance) Change: When the external conditions change, the equilibrium may be destroyed, and a new chemical equilibrium is established under new conditions.

Content, conversion rate, etc., these quantities no longer change a certain balance.

The quantity, mass, and concentration of substances remain unchanged and are in a certain equilibrium.

Option A: There is only 1 gas in the container, the equilibrium moves no matter how it moves, or only gas A, and the average molecular weight of all gases remains the same.

Option B: Anyway, analyze the CD first.

Option C: If C is solid, then B must no longer be liquid or solid, otherwise the answer will be the same as A.

3a(g)==(reversible sign)3b(g)+c(s) As the temperature increases, the equilibrium shifts positively, and the total mass of the gas decreases, while the total mass of the gas remains the same, so the average relative molecular mass decreases. （m=m/n）

Option d: 3a(g)== (reversible sign)3b(g)+c(g) The temperature increases, the equilibrium shifts positively, the total mass of the gas is conserved, and the amount of total matter increases, so the average relative molecular weight decreases.

i.e. get the answer cd. b The answer is wrong.

By the way, the school you attend must be a very good school.

Analysis: Rise in temperature Equilibrium shifted to the right.

a If BC is solid and only A is a gas, then the average relative molecular mass of the gas should be constant.

b If BC is a gas, it is okay to increase the amount of the substance and decrease the average molecular weight according to the same mass of the gas.

If the B gas C is solid, it is also possible that the average molecular weight will be smaller.

Therefore, option B is wrong.

c If B is not a gas and only A is a gas, then the average relative molecular mass of the gas should be constant.

Because the positive reaction is endothermic and the temperature increases the equilibrium moves in a positive direction, the average relative molecular mass of the gas now has a tendency to decrease, m (mixed) = m (mixed) n (mixed).

A, B, and C are solids, then only A is a gas in the whole reaction system, and in any case, the relative molecular mass of the gas is constant to the relative molecular mass of A.

b is wrong (because cd is correct).

C, C is solid, B is a gas, then the amount of gaseous substances before and after the reaction remains the same, but the gas mass decreases, because m (mixed) = m (mixed) n (mixed), since n mixing is unchanged, m mixing is reduced, so the ratio decreases, c can.

D and BC are both gases, so the total mass of the mixed gas in the reaction remains unchanged, but the amount of gaseous substances is increasing, so the ratio is still smaller.

As the temperature rises, the reaction shifts to the right (is it constant capacitance?) In the case of the same volume, the relative molecular mass becomes smaller, then the total gas mass also decreases, and the conservation of materials can be known, and CD is selected

Put 10 mol a and 5 mol b into a closed container with a volume of 10 l, and the reaction occurs at a certain temperature: 3a(g)+b(g) === 2c(g), in the first 2 s, the average rate of consumption of a is mol·l-1·s-1, then at 2 s, there is mol a in the container, and the amount concentration of c at this time is

Specification Answer] 3a(g) +b(g) ===2c(g).

Starting concentration (mol l) 0

Transformation concentration (mol l).

Concentration at 2 s (mol l).

Then at 2 s, n(a) = mol l 10 l = molc(c) = mol l

Answer: mol l

The reaction is endothermic. As the temperature increases, moving to the right, the average relative molecular mass of the gas becomes smaller, the gas mass decreases or the number of gas moles increases: 1 To increase the number of gas moles purely (i.e., the gas mass does not decrease), then y and z must be gases 2 To reduce the gas mass, if y is a solid, z is a gas, because the number of gas moles decreases, the average relative molecular weight of the gas may become smaller; If z is a solid and y is a gas, it fits the topic; If Y and Z are solids, the average relative molecular mass of the gas remains unchanged (still the relative molecular mass of X) In summary, C should be chosen

Breakthrough - The pressure ratio at equilibrium is 6:5

The original gas is 12mol, and it can be seen that there is 10mol of gas after the reaction equilibrium, and it can be seen through the reaction equation that only 1mol N2 and 3mol H2 participate in the reaction, which is converted into 2mol NH3

So the following can be solved......Your x=1mol

c（nh3）=2/10=

The h2 conversion rate is 3 8=

A heats up, the equilibrium proceeds in the direction of the reverse reaction, the amount of the substance increases, the mass does not change, and the average relative molecular mass decreases according to m=m n.

b equilibrium shifted left, no2 concentration increased, no2 had color, color deepened c balance shifted left, n2o4 decreased, and conversion rate increased (the equation for this question should be written n2o4=2no2).

d balance shifted to the left, no2 increased, volume fraction increased, d error.

d is uncertain because the mass of matter of NO2 increases at the same time as the total mass of matter increases.

First, the temperature rises, and the equilibrium shifts to the left.

A The amount of substance increases, the mass remains unchanged, according to M=M n, the average relative molecular weight decreases, B NO2 concentration increases, NO2 has color, color deepens C, the equilibrium shifts left, and the conversion rate of N2O4 increases.

d Equilibrium shifted to the left, NO2 increased, and volume fraction increased **d