Topics for Test – Chemical Equilibrium
- Graphs representing systems in equilibrium
- Homogeneous equilibrium
- Heterogeneous equilibrium
- Dynamic equilibrium
- How to write equilibrium concentration expressions for heterogeneous equilibrium
- What does the magnitude of Kc or Keq tell you
- Equilibrium constant for reactions with 2 or more elementary steps
- Multiplying an equation by a coefficient ‘n’ changes Kc to Kc raised to n
- When Kc = 1 what does it mean?
- Application of Le Chateliers principle on systems in equilibrium
- Shift in equilibrium when there is a [concentration] change
- Shift in equilibrium when concentration is changed by changing volume
- Shift in equilibrium when an inert gas is added to the reaction mixture
- Shift in equilibrium when products are removed from the closed equilibrium system
- Shift in equilibrium when the number of moles of reactants and products are not equal for gaseous system
- Shift in equilibrium when heat is added or removed in an exothermic or endothermic reaction
- Shift in equilibrium and catalyst for a reversible reaction
- Problems – When the equilibrium expression is a perfect square
- Problems – When K is very very small (applying 100th rule)
- Problems – When the equilibrium expression is not a perfect square and the use of quadratic equation
- Problems – When a stress is applied to a system in equilibrium (Le Chatliers principle) new concentration of reactant or product
- Entropy – definition and prediction based on state of matter, temperature of reactants and products, # of moles of reactants and products
- Spontaneous reactions
- Gibbs Helmoltz equation and free energy
- What is the significance of free energy?
- What are the conditions for spontaneity of chemical reactions
- Calculation of Kc from free energy DG = -2.303 RTlog Kc, DG = DH – TDS
- Temperature at which a system attains equilibrium DG and equilibrium when value = 0
- DG and equilibrium when value < 0 = -ve
- DG and equilibrium when value > 0 = +ve
- DG = 0 the system is in equilibrium.
Solubility Product Topics
- Equilibrium of sparing soluble salts
- Solubility product constant Ksp
- Determination of Ksp from molar solubility
- Ion product Vs Solubility product
- Determining molar solubility from Ksp
- Common ion effect, qualitative explanation and calculation
- Predicting precipitation, problems
- Selective precipitation of halides, sulfides, hydroxides, metals
- Application of knowledge of Ksp
- Use of complex ion formation in qualitative analysis
- Separation of metal ions using Ksp