Equilibria

• If the temperature of a reaction at equilibrium increases, the equilibrium shifts to oppose the increase. If the forward reaction is exothermic, the equilibrium shifts to the left to decrease the temperature.
• Pressure only affects moles of gas, if the volume and temperature are constant.
• If the pressure increases, the equilibrium will shift to oppose this and decrease the pressure. It would shift to the side with the lower number of moles.
• If the concentration of a reactant is increased, the equilibrium will shift to oppose this change by shifting to the right to use up the reactants and make more products.
• A catalyst has no effect on the position of equilibrium. It speeds up the forward and backward reaction at equal rates so equilibrium is reached faster.
• In industry, yield and rate must be considered.
• In industry, high temperature can have high energy costs but low temperature can have a slow rate.
• In industry, high pressure can increase yield but high pressure equipment it is expensive to build and operate.
• In industry, low pressure means there will be a low rate of reaction.
• Kc is an equilibrium constant. It is constant at a constant temperature.