I don't believe any of our teachers speak Russian. Using Google, I have translated your question as follows, but some of the words do not translate properly:
Calculate the equilibrium constant of reaction PCl5(g) ↔ PCl3(g) + Cl2(g). at a certain temperature, it is known that at the moment when the equilibrium prodissotsiirovalo 50% of the phosphorus chloride (V), and the initial concentration of the substance was ravna2, 8 mol/liter. In what direction will the balance shift, if: a) you reduce the volume of the system
b) you increase the concentration of chloride, PCl3?
Justify your answer.
(a) Since more moles are formed when PCl5 dissociates, decreasing the volume will tend to make the reaction go to the left, to reduce the number of moles present. The reaction proceeds in the direction that reduces the pressure increase.
(b) Increasing the concentration of PCl3 will also tend to make the reaction go to the left, to somewhat reduce the concentration of the added species. (The backward reaction rate increases)
Both situations can be explained using Le Chatelier's principle, which is explained at:
Обе ситуации можно объяснить, используя принцип Ле Шателье.
Я надеюсь, что вы можете понять мой английский ответ выше.
drwls, a man of many talents.
;-) but chemistry is not among them.
I don't know Molar from molal or bicuspid.