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For the AP exam, there are two major areas/understanding of Solid Equilibrium as follows:
1)Certain compounds will completely dissolve in water and other will not (or the reverse, ions will always come together to form solid)
- This is the basis of the AP reaction section and knowing if you will be getting a participate from addition of two aqueous solution.
- In 1st year, we call these types of reactions, Double Replacement reactions or more specifically Double Replacement Reaction - Solid Formed. Here is link to 1st year information including how to show net ionic reactions, [Notes on 1st Year Double Replacement Reactions]. You will be replacing your APSolubilityRules for 1st Years Solubility Table.
- You will be able to write balanced complete chemical reaction and net ionic reactions when two aqueous solution comes together. Also be able to do stoichiometry on these types of chemical reactions.
- The above information assumes that once the participate is formed it does not "redissolve". Except for a small number of substances, is NOT TRUE.
2) In reality, everything dissolves (or comes together) somewhat since most dissolving processes (not a chemical reaction) are reversible reaction.
- With reversible reactions comes Equilibrium. This type of Equilibrium has a special name, Solid Equilibria. The equilibrium constant also has a special name called Ksp.
- All the procedures and rules for all the other types of Equilibrium are also followed in Solid Equilibrium.
- The "big" difference here that one of the components of the chemical reaction (will actual be the product, more details later in AP book) will be a solid. Thereby, this component is not part of the equilibrium constant. Therefore, all Ksp expressions will not have a denominator.
- You will see the word, Solubility (usually with the name of solid after it). It means how much of that solid has dissolved not the amount of each ion that is "made". Determining actual concentrations of each ions in solution also require stoichiometry.
Here are the main sections of Solid Equilibrium including Zumdahl (AP book) reference sections and a few HW assignments (all answers in back of book):
- Calculate Ksp from Solubility data or Calculate Solubility from Ksp
- Section 15.6 Pg745-top of Pg750
- Good examples in book of both "ways" of calculating problems.
- Will need Ksp table (Pg747 or back of book in blue pages)
- Do Pg770 #81a, 83, 85a
- Comparing several Ksp
- Pg750 (part of Section 15.6)
- Most questions are qualitative but require calculations
- Pg770 89a
- Ksp with Common Ion Effect and Special Case of Ions affecting pH
- Pg751-752 for Ksp and Common Ion Effect and Pg753-top of 754 on pH & Solubility
- Exactly like Acid/base equilibria (buffer solutions) but no H-H equation. Remember need to check 5% rule.
- Do Pg770 #91(all parts), 93, 95
- Precipitation (all can look at Section 4.5-4.7 in AP book for details)
- Predicting participation reaction / writing balanced complete precipitation reaction and net ionic reaction(as stated above in Part 1)
- Besides 1st year material, can look at Section 4.5-4.6 in AP book for review
- Calculation for precipitation reaction (Section 4.7) including solid solubility (Section 15.7)
- Go examples of math calculations for precipitation conditions in Section 15.7 on Pg754-757
- Do Pg181 #31 (also write balance complete reaction) - no math here
- Do Pg770 #97,99,101 - will require math