A concentration of PCl5(g), 4,0 mol/L, it appears that the proceeding PCl5(g) => PCl3(g) + Cl2(g) is achieved with a degree of balance of 20%. In these conditions, calculate the value of chemical equilibrium

To calculate the value of the chemical equilibrium in this reaction, we need to determine the concentrations of PCl3(g) and Cl2(g) at equilibrium.

Given:
Initial concentration of PCl5(g) = 4.0 mol/L
Degree of balance = 20%

First, let's determine the equilibrium concentration of PCl5(g). The degree of balance gives us the proportion of reactant that has reacted at equilibrium. In this case, it is 20%, so only 80% of PCl5 is left at equilibrium.

Equilibrium concentration of PCl5(g) = Initial concentration of PCl5(g) * (1 - Degree of Balance)
= 4.0 mol/L * (1 - 0.20)
= 4.0 mol/L * 0.80
= 3.2 mol/L

Next, let's calculate the equilibrium concentration of PCl3(g) and Cl2(g). Since one mole of PCl5 produces one mole of PCl3 and one mole of Cl2, the equilibrium concentration of PCl3(g) and Cl2(g) will be the same.

Equilibrium concentration of PCl3(g) = Equilibrium concentration of Cl2(g)
= Degree of Balance * Equilibrium concentration of PCl5(g)
= 0.20 * 3.2 mol/L
= 0.64 mol/L

Therefore, the value of the chemical equilibrium (Kc) for this reaction is given by the ratio of the equilibrium concentrations of PCl3(g) and Cl2(g) to the equilibrium concentration of PCl5(g).

Kc = ([PCl3(g)] * [Cl2(g)]) / [PCl5(g)]
= (0.64 mol/L * 0.64 mol/L) / 3.2 mol/L
= 0.4096 mol^2/L^2 / 3.2 mol/L
= 0.128 mol/L

Hence, the value of the chemical equilibrium (Kc) is 0.128 mol/L.