How does decreasing the pressure in a system at equilibrium containing gaseous reactant and products affect the position of equilibrium?

According to Le Chatelier's principle, when the pressure in a system at equilibrium is decreased, the system will shift in the direction that produces more moles of gas in order to counteract the change. This means that if the reactants and products in the system contain different numbers of moles of gas, the equilibrium position will shift towards the side with more moles of gas in order to increase the pressure back to its original value.

For example, if a system at equilibrium contains gaseous reactants and products where the reactants have more moles of gas than the products, decreasing the pressure will cause the equilibrium position to shift towards the products in order to increase the total moles of gas and therefore increase the pressure back to its original value.

On the other hand, if the products have more moles of gas than the reactants, decreasing the pressure will cause the equilibrium position to shift towards the reactants in order to increase the total moles of gas and therefore increase the pressure back to its original value.

Overall, decreasing the pressure in a system at equilibrium containing gaseous reactants and products will cause the equilibrium position to shift in the direction that produces more moles of gas in order to counteract the change in pressure.