5.1.2 How far?

Question 1

How does the expression for Kc differ depending on whether the equilibrium is homogenous or heterogeneous?

Answer 1

Homogeneous

• all eq species have same state
• all species concentrations in Kc expression

Heterogeneous

• species in different states at equilibrium
• Kc only has (g) and (aq) species as the conc of solids and liquids are essentially constant

Question 2

partial pressure =

Answer 2

mole fraction x total pressure

Question 3

what happens to an equilibrium when you alter concentration and pressure

Answer 3

the position of the equilibrium changes in order to keep the equilibrium constant the same

Question 4

why is K only affected by temperature?

Answer 4

because when you increase temp, the endothermic reaction is favoured and more of one side of the equ. is made (reactants or products). This means K shifts to one side or the other. When you change pressure or conc, the change is immediately counteracted, so K remains the same