3.2.3 equilibrium

occurs when the forward and backward reactions are occurring at equal rates concentrations of reactants and products stays constant and reaction is continuious

increasing > shits to endothermic (+) direction to try to reduce the temperature by absorbing heat decreasing > shits to exothermic (-) direction to increase temperature + effect on yield

may give a higher yield but will also result in slow rates of reaction

increasing pressure > side with fewer moles of gas to oppose the change & reduce the pressure decreasing pressure > side with more moles of gas if number of moles is same on both sides, then changing pressure will have no effect on position of equilibrium

may give a higher yield & faster rate but expensive to maintain conditions

increasing OH- ion concentration causes equilibrium to shift to forward direction to remove OH- ions equil shifts to right, giving higher yield of I- and IO- adding H+ ions reacts with OH- and reduces their concentration so equil > left

no effect on position as it speeds up rate of forwards and backwards equally

N2 + 3H2 > 2NH3 450C iron catalyst 200-1000 atm

stage 1: S + o2 > SO2 (g) stage 2: SO2 + 0.5O2 > SO3 450C 1-2 atm V2O5 catalyst

Kc = conc of products / conc of reactants mol dm-3