2.10 - Equilibrium

Define reversible

reaction going in forward and reverse direction

Define equilibrium

reversible reaction where amount of reactant/product constant

Define dynamic(equilibrium)

rate of forward reaction equal to rate of reverse reaction

Define Kc

Kc = ([C]^c x [D]^d) / ([A]^a x [B]^b)

What does Le Chatelier’s Principle state?

when conditions affecting position of dynamic equilibrium changed, equilibrium position respond to oppose change

What does Le Chatelier’s principle do?

predict direction position of equilibrium shifts under varying conc/temp/pressure with or without catalyst but not extent

Why is ammonia production in Haber process at a compromise temperature?

low temp optimum for maximum % yield of ammonia but ROR slow so compromise needed

Operating conditions of ammonia

450C and 200atm

What are the temperature and pressure used industrially in Haber process called?

compromise conditions

What catalyst is added to increase ROR in Haber process?

finely divided iron as heterogeneous catalyst

Three steps of the contact process

making SO2, converting SO2 into SO3, converting SO3 into H2SO4

How is sulfur dioxide made?

S(s) + O2(g) = SO2(g)

How is sulfur dioxide converted into sulfur trioxide?

2SO2(g) + O2(g) = 2SO3(g) (reversible)

Conditions of reaction where sulfur dioxide converted to sulfur trioxide

450C, 2atm, Vanadium(V) oxide catalyst

How is sulfur trioxide converted into sulfuric acid?

H2SO4(l) + SO3(g) = H2S2O7(l) and then H2S2O7(l) + H2O(l) = 2H2SO4(l)

Why can’t you just add water to sulfur trioxide to form sulfuric acid?

reaction uncontrollable and creates corrosive mist of sulfuric acid

What is produced by dissolving sulfur trioxide in concentrated sulfuric acid?

oleum

What is a way to move equilibrium to the right by concentration in contact process and economical benefit?

add excess of O2 to shift position of equilibrium right, cheap as O2 comes from air

Why is the contact process only done at pressure close to 1atm?

99.5% conversion rate, improvement isn’t worth expense of producing higher pressures