Why does the pressure increase and the balance move in the direction of volume decrease?

Increasing the pressure will reduce the volume of the container, and the balance will move in the direction of reducing the gas volume. Pressurization can be understood as changing the mass concentration of a substance. In other words, if the mass concentration of a substance increases, the equilibrium direction will inevitably move in the direction of volume reduction.

For example, a piston in the middle of a closed container divides the container into two chambers. The process of pressurization is to inject air into a chamber, and the process is completed instantly. When the pressure in this chamber increases, the piston will move, which has the effect of reducing the volume of the other chamber.

Extended data:

Balanced motion

Under the condition of chemical reaction, the reversible reaction changes from one equilibrium state to another due to the change of reaction conditions, which is called the movement of chemical equilibrium. The fundamental reason of chemical equilibrium shift is that the positive and negative reaction rates are not equal, and the result of equilibrium shift is that the reversible reaction reaches a new equilibrium state, at which time the positive and negative reaction rates are equal again (which may or may not be equal to the original rate).

The main factors affecting the chemical equilibrium shift are concentration, temperature and pressure.

equilibrium process

1, process (dynamic angle)

From the kinetic point of view, at the beginning of the reaction, the concentration of reactants is large and the concentration of products is small, so the positive reaction rate is greater than the reverse reaction rate. With the progress of the reaction, the reactant concentration decreases and the product concentration increases, so the positive reaction rate decreases and the reverse reaction rate increases.

When the positive and negative reaction rates are equal, the concentration of each substance in the system remains unchanged and the reaction reaches equilibrium. At this point, the system is in a state of dynamic equilibrium, which does not mean that the reaction stops completely at this point.

2. Process (micro-angle)

Microscopically, it is the equilibrium phenomenon caused by the fact that the fracture rate of chemical bonds in reactant molecules is equal to that in products in reversible reaction.

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