Dissociation of Phosphorus Pentachloride decreases with increasing pressure - QS Study
QS Study

At constant temperature, the dissociation of Phosphorus Pentachloride decreases with increasing pressure.

The reaction: PCl5↔ PCl3 + CO2

no. of moles →  1          1          1

At constant temperature, the effect of pressure change depends on a number of moles of reactant and product. In this reaction the number of moles produces is higher than reactant. For that, the dissociation decreases with increasing pressure.