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Anonymous users2024-02-06The Second Middle School of Guannan County, Jiangsu Province, the Second Middle School of Guannan County, Jiangsu Province, the Second Middle School of Guannan County, Jiangsu Province, the Second Middle School of Guannan County, Jiangsu Province.
Lin Yi Lin Yi Lin Yi Lin Yi.
For chemical reactions without the participation of gases, the change in reactant concentration when changing the pressure is small and negligible, so the chemical reaction rate is affected.
No effect. For reactions with gas participation, the textbook reads: the pressure increases, and the chemical reaction rate increases; Decreasing the pressure decreases the rate of chemical reactions, but the increase in pressure here refers to the reduction of volume, and the decrease in pressure refers to the increase of volume.
In the specific topic, it is necessary to analyze what is the reason for the change in pressure, and whether this cause can cause the change in gas concentration. Specifically, there are the following situations.
1.At a constant temperature, the volume is compressed.
The pressure increases. The concentration increases.
The reaction rate increases. Conversely, the volume of the vessel is increased, and the reaction rate decreases.
Explanation: At constant temperature, the volume is compressed.
Percentage of activated molecules.
No change, but per unit volume.
The number of internally activated molecules increases, the effective collision probability increases, and the reaction rate increases. Conversely, the volume of the vessel is increased, and the reaction rate decreases.
2.At constant temperature, for constant volume closed containers:
Filled with gas reactants.
The concentration of gas reactants increases (the pressure also increases) and the reaction rate increases.
Explanation: When the volume remains the same, the gas reactant is charged.
The percentage of activated molecules remained unchanged, but the number of activated molecules per unit volume increased.
Increased chance of effective collisions.
The reaction rate increases.
Fill with gas that does not participate in the reaction.
The total pressure in the container increases
The concentrations of each substance did not change
The reaction rate is unchanged.
Explanation: When the volume is unchanged, the number of activated molecules and the percentage of activated molecules filled with gases that do not participate in the reaction remain unchanged.
The effective collision chance remains the same
The reaction rate is unchanged.
In short, when analyzing the effect of pressure change on the chemical reaction rate, the key is to see whether the gas concentration changes: if the gas concentration changes, the chemical reaction rate must change; If there is no change in the concentration of the gas, the rate of the chemical reaction does not change. At the same time, it should be noted that the commonly referred to as pressure increase refers to compression and pressurization.
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Anonymous users2024-02-053H2 + N2 = 2NH3 The pressure is a multiple of the beginning, then the amount of total matter is (1+3).
The amount of N2 species that is given to react is x
3-x）+(1-3x)+2x =
x =v(h2) =
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Anonymous users2024-02-04For gases, if other conditions remain constant, increasing the pressure is to increase the amount of reactants per unit volume, that is, to increase the concentration of reactants, so that the rate of chemical reactions can be increased. The pressure is reduced and the reaction rate is slowed down.
For chemical reactions with gas participation, when other conditions remain unchanged (except volume), the pressure is increased, that is, the volume decreases, the concentration of reactants increases, the number of activated molecules per unit volume increases, the number of effective collisions per unit time increases, and the reaction rate accelerates. Otherwise, it decreases.
If the volume is constant, the rate of the pressurized reaction (adding gases that do not participate in this chemical reaction) will not change. Because the concentration does not change, the number of activated molecules per unit volume does not change. However, when the volume remains the same, the reactants are added, which is also pressurized, and the concentration of reactants is increased, and the rate will also increase.
If the volume is variable, the constant pressure (adding gases that do not participate in this chemical reaction) reduces the reaction rate. Because the volume increases, the amount of reactant substances does not change, the concentration of reactants decreases, and the number of activated molecules per unit volume decreases.
The rate of a chemical reaction is an indication of how fast a chemical reaction proceeds. It is usually expressed as the change value (reduction value or added value) of the concentration of reactants or products per unit time, and the reaction speed is related to the nature and concentration of the reactants, temperature, pressure, catalyst, etc., and if the reaction is carried out in solution, it is also related to the properties and amount of solvents.
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Anonymous users2024-02-03Obviously this is wrong.
For example, in the case of constant volume, when a gas that does not participate in the reaction is added to the chemical reaction, the pressure increases, while the chemical reaction rate remains unchanged.
Here's why: The rate of a chemical reaction is defined as the change in the concentration of reactants (or products) per unit of time. Under the above conditions, the amount of each reactant and the product does not change, and the constant volume does not change, so their concentration does not change, so the chemical reaction rate also does not change.
PS: To consider the change in the rate of chemical reaction, we should start from its definition, and analyze the change in concentration per unit time, and then we can understand the change in the reaction rate.
1) Yes, as long as it is the substance in the equation.
2) The reaction rate ratio of O2 and SO2 is 11:8, so when the rate of SO2 generation is, the rate of O2 consumption is. >>>More
Generally speaking, the higher the temperature, the faster the reaction, the lower the temperature, the slower the reaction, which is not only a familiar phenomenon for chemists, but also a common sense of people's life, the room temperature is high in summer, and the food is easy to rot and deteriorate, but the food in the refrigerator can be stored for a longer time. The oxidation reaction rate of steel at room temperature is extremely slow, which is greatly accelerated with the increase of temperature, and a large amount of iron oxide scale has been produced when it is red-hot. The reaction of hydrogen and oxidation to form water can not be detected for several years at room temperature, and if it is heated to 973K, it will be completed instantaneously at the rate of **. >>>More
Answer: Obviously this is wrong.
For example, in the case of constant volume, a gas that does not participate in the reaction is added to the chemical reaction, and the pressure increases, and the chemical reaction rate. >>>More
At the time of baking, milk carton baking powder is mixed with flour, or vinegar and baking soda are mixed, and then the "volcanic effect" occurs, and the process undergoes a double displacement or metathesis reaction. The reaction process between vinegar and baking soda is roughly as follows: HC2H3O2(AQ) +NaHCO3(AQ) NAC2H3O2(AQ) +H2O(AQ) +CO2(G).
After the trim equation, look at the valency change.