[19.1] the equilibrium constant Kc - part 2

Question 1

how do you calculate Kc when you don’t have the equilibrium moles?

Answer 1

• use ICE
• I = initial number of moles
• C = change in moles
• E = equilibrium moles
• use info in question to calculate conc at equil

Question 2

what are homogenous equilibria?

Answer 2

when all reactants and products are in the same phase

Question 3

what is heterogenous equilibria?

Answer 3

when there are species that have different phases / states

Question 4

in heterogenous equilbria, what do you have to consider with solids and liquids?

Answer 4

• the concentration of solids and liquids is essentially constant, so is omitted from the expression for Kc
• ie. they are automatically incorporated within the equilibrium constant

Question 5

what goes on in equilibrium state?

Answer 5

• reaction is reversible
• system is closed
• equilibrium is dynamic
• equilibrium position shifts if conditions change

Question 6

what species does Kc include?

Answer 6

• (g)
• (aq)