Le Chatelier's principle states that when a system at equilibrium is subjected to a change in pressure, temperature, or concentration of reactants or products, the system will adjust itself to counteract the change and re-establish a new equilibrium.When the pressure is increased in a system that involves a gaseous reactant and/or product, the equilibrium will shift in the direction that reduces the pressure. This means that the system will favor the side with fewer moles of gas.To understand this, consider a hypothetical reaction:aA g + bB g cC g + dD g Here, A and B are reactants, and C and D are products. The lowercase letters a, b, c, and d represent their respective stoichiometric coefficients.If the pressure is increased, the system will try to minimize the effect of this change by shifting the equilibrium in the direction that has fewer moles of gas. If the total moles of gaseous reactants a + b are greater than the total moles of gaseous products c + d , the equilibrium will shift towards the products. This will result in an increase in the concentration of products and a decrease in the concentration of reactants.On the other hand, if the total moles of gaseous reactants a + b are less than the total moles of gaseous products c + d , the equilibrium will shift towards the reactants. This will result in an increase in the concentration of reactants and a decrease in the concentration of products.In summary, when the pressure is increased in a system involving gaseous reactants and/or products, the equilibrium will shift in the direction that has fewer moles of gas, according to Le Chatelier's principle. This will cause a change in the equilibrium concentrations of the reactants and products, either favoring the formation of products or reactants depending on the stoichiometry of the reaction.