Answer:
An equilibrium reaction is one in which the forward and reverse reactions occur at the same rate, resulting in no net change in the concentrations of the reactants and products over time. The yield of products in an equilibrium reaction depends on the reaction conditions, which can be altered by changing the concentration, pressure, temperature, or the addition of a catalyst. The factors that cause yield to increase or decrease in an equilibrium reaction include:
Concentration of reactants and products: Increasing the concentration of reactants can shift the equilibrium to favor the formation of products, while increasing the concentration of products can shift the equilibrium to favor the formation of reactants.
Pressure: Increasing the pressure of a gaseous equilibrium reaction can shift the equilibrium to favor the side with fewer moles of gas.
Temperature: Changing the temperature of an equilibrium reaction can cause a shift in the equilibrium position. An exothermic reaction favors the reactants at low temperature and the products at high temperature. On the other hand, an endothermic reaction favors the reactants at high temperature and the products at low temperature.
Catalyst: A catalyst can increase the rate of the forward and reverse reactions equally, without changing the equilibrium position. This can result in a higher yield of products in a shorter time period.
In summary, the factors that affect yield in an equilibrium reaction are changes in concentration, pressure, temperature, and the presence of a catalyst.