Presentation on theme: "K c and equilibrium. What does K c signify? If K c = 1 then the position of equilibrium is half way between products and reactants If K c > 1 then the."— Presentation transcript:
K c and equilibrium
What does K c signify? If K c = 1 then the position of equilibrium is half way between products and reactants If K c > 1 then the equilibrium lies to the right. If K c < 1 then the equilibrium lies to the left.
Temperature and K c Increasing temperature shifts the equilibrium to the endothermic direction (ΔH +ve) Decreasing temperature shifts the equilibrium to the exothermic direction (ΔH –ve) Changing the position of the equilibrium actually depends on the value for K c, which only changes it’s value only with changes in temperature.
Changing Concentration Changing the concentration of a reactant or product doesn’t change the K c value. Changing the concentration will force the equilibrium to move in accordance to le Chatalier’s principle.
Changing Pressure Similarly changing pressure doesn’t change the value of K c. The equilibrium shifts to return the reaction to the equilibrium point.
Catalysts Catalysts do nothing. They speed up both reactions equally, so don’t affect the value of K c.
Remember! Rate constants tell us how FAST a reaction is. – Calculated from experimental data Equilibrium constants tell us how far a reaction can go – Calculated from an overall balanced equation.