equillibrium

• The equilibrium constant is the ratio of products to reactants at equilibrium.
• A reaction with an equilibrium constant less than one has more reactant present compared to product.
• A reaction with an equilibrium constant greater than one has more product formed compared to reactant.
• If the concentration of all species involved in a chemical equation doubles, then K will also double.
• An endothermic reaction will have a lower temperature when it reaches equilibrium, while an exothermic reaction will have a higher temperature when it reaches equilibrium.
• Increasing temperature increases the rate of reactions that are exothermic (release energy) but decreases the rate of endothermic (absorb energy).
• Increasing pressure favors reactions that form fewer moles of gas (exothermic) or increase the number of moles of gas (endothermic).
• Le Chatelier's principle states that if a system at equilibrium experiences a change, the position of equilibrium shifts so as to counteract the effect of the change.
• When a catalyst is added to a reversible reaction, the rate increases but the equilibrium point remains unchanged.
• Le Chatelier's Principle states that if a system at equilibrium experiences a change, the position of equilibrium shifts so as to counteract the effect of the change.
• Adding a catalyst does not affect the value of K.
• An equilibrium constant greater than one indicates that there are more products present compared to reactants.
• A reaction with an equilibrium constant greater than one has more product formed compared to starting materials.
• The equilibrium constant is equal to the ratio of products over reactants raised to their respective stoichiometric coefficients.
• The equilibrium constant can be used to determine whether a reaction is favorable or unfavorable by comparing its value with the concentrations of reactants and products.
• A forward reaction has a positive delta G, indicating that free energy is released during the process.
• If [A] = [B], then the equilibrium lies exactly halfway between reactants and products.
• The equilibrium constant (K) can be calculated using the expression Q = KP/[R]^2 where P is the total pressure and [R] is the concentration of reactants.
• If the forward reaction has a higher enthalpy than the reverse reaction, then the forward reaction will have a lower activation energy and proceed faster.
• A catalyst speeds up both the forward and backward reactions equally, resulting in no net change in the overall rate of reaction.
• If the concentration of a substance changes during a chemical reaction, it will shift towards the side where its concentration decreases.
• If the concentration of products is higher than the concentration of reactants, then the equilibrium constant will have a value greater than one.
• When the equilibrium constant is less than one, it means that the concentration of reactants is higher than the concentration of products.
• Increasing temperature increases the rate of forward reactions but decreases the rate of reverse reactions.
• Endothermic reactions require more energy than they release, while exothermic reactions release more energy than they absorb.
• An endothermic reaction absorbs heat from the surroundings to occur, while an exothermic reaction releases heat into the surroundings as it occurs.
• When a substance in an equilibrium reaction is added or removed from the system the reaction will shift to counter the change
• When the pressure of a system in dynamic equilibrium is changed the equilibrium will shift in the direction that reverses that change
• When the temperature of a system in a dynamic equilibrium is changed the equilibrium will shift in the direction that reverses that change
• For reversible reactions, the catalyst lowers the activation energy for BOTH forward & reverse reactions
• What would happen to the equilibrium position if the pressure was decreased for the reaction below? 2H2O+2Br2+113kJ->4HBr+O2


  it will shift towards the products
• How is the reaction rate affected when H2 is removed?

  the reverse rate is temporarily faster
• Which stress will shift the equilibrium to lower the amount of NH3?

  add heat
• What effect does a decrease in temperature have on an endothermic equilibrium reaction?


  it shifts equilibrium towards the reactants