Chemical Equilibrium Lab
Chemical equilibrium is the point at which the concentrations of reactants and products do not change with time. It would appear as if the reaction has stopped, but in fact, the rates of the forward and reverse reactions are equal, causing the reactants and products to be created at the same rate. This can be expressed mathematically in the form of the equilibrium constant. The following is the general equation for a reversible chemical reaction: aA+bB →cC+dD Equation 1
Equation 2 below will give the equilibrium constant, Keq, for this general reaction, where the square brackets refer to the molar concentration of the reactants and products at equilibrium.
K_eq= (〖[C]〗^c [D]^d)/([A]^a [B]^b )
Equation 2
Changes that are made to a system, such as concentration and temperature, at equilibrium may be considered a stress. This could cause the rated of the forward the reverse reactions to change until equilibrium is again established. After may studies of equilibrium systems, Henri LeChâtelier created the LeChâtelier’s principle. It can stated as follow: A change in one of the variables that describe a system at equilibrium produces a shift in the position of the equilibrium that counteracts the effect of this change. Basically, if a system is subject to a stress, it would react in a way to reduce that stress. While LeChâtelier’s principle is a qualitative approach to predicting and interpreting shifts in equilibrium system, a quantitative approach can be utilized by using the Keq of the reaction and the reaction quotient, Q. The reaction quotient helps in figuring out which direaction a reaction is likely to proceed, given either the pressures or the concentrations of the reactants and the products, and it is calculated using the same formula as Keq (Equation 2).
Equation 2 below will give the equilibrium constant, Keq, for this general reaction, where the square brackets refer to the molar concentration of the reactants and products at equilibrium.
K_eq= (〖[C]〗^c [D]^d)/([A]^a [B]^b )
Equation 2
Changes that are made to a system, such as concentration and temperature, at equilibrium may be considered a stress. This could cause the rated of the forward the reverse reactions to change until equilibrium is again established. After may studies of equilibrium systems, Henri LeChâtelier created the LeChâtelier’s principle. It can stated as follow: A change in one of the variables that describe a system at equilibrium produces a shift in the position of the equilibrium that counteracts the effect of this change. Basically, if a system is subject to a stress, it would react in a way to reduce that stress. While LeChâtelier’s principle is a qualitative approach to predicting and interpreting shifts in equilibrium system, a quantitative approach can be utilized by using the Keq of the reaction and the reaction quotient, Q. The reaction quotient helps in figuring out which direaction a reaction is likely to proceed, given either the pressures or the concentrations of the reactants and the products, and it is calculated using the same formula as Keq (Equation 2).