Recent Changes

For this whole topic, students need to do problems, problems, problems!!
Indicators
The full-length clip GW has but it'sis too big here. You can get if off me if you want it.can, however, find it on Q drive at Science/Chemistry/year 13/3.16aqueous 91392/Resources

http://www.chemguide.co.uk/physical/acidbaseeqia/phcurves.html
For this whole topic, students need to do problems, problems, problems!!
Indicators
The full-length clip GW has but it's too big to upload here. You can get if off me if you want it.

Revision of pH and comparison with KA and KB: A "put in the correct order" exercise.(answer on page one and jumbled on second page)
{pH.pKadoc.doc}
Titrations curves
Chemguide web site
http://www.chemguide.co.uk/physical/acidbaseeqia/phcurves.html
For this whole topic, students need to do problems, problems, problems!!

After this clip it will probably be necessary to emphasise the fact that the only source of silver ions is from the silver iodide and so its value represents the concentration of silver iodide in a solution that contains iodide ions from another source.
Lots of practice with problems is necessary.
Good experiment in Cooper and Abbott -2006 edition, Year 13 Chemistry Practical Workbook page 260 (beware of copyright restrictions)
Complex ions and solubility
e.g.

Dissolving: a "put in the correct order" exercise. (answer is the first page and jumbled is on the second page)
{Dissolving.doc}
KA andand KB : for example.

Revision of pH and comparison with KA and KB: A "put in the correct order" exercise.(answer on page one and jumbled on second page)
{pH.pKadoc.doc}

http://chemed.chem.wisc.edu/chempaths/GenChem-Textbook/The-Solubilities-of-Salts-of-Weak-Acids-977.html
Acid-Base Stuff
Species in solution: Cooper and Abbott -Year 13 Chemistry Practical Workbook page 266 "Species in Aqueous Solution" (caution with copyright)
This is good for revising/introducing the weak acids and bases
Dissolving: a "put in the correct order" exercise. (answer is the first page and jumbled is on the second page)
{Dissolving.doc}
KA and KB : Introduce these using reactions of ethanoic acid with water and ammonia and water for example.

Solubility product expressions
What happens when something dissolves?
Complex ions and solubility
e.g.
from: from this web site:
https://www.boundless.com/chemistry/acid-base-equilibria/complex-ion-equilibria-and-solubility/complex-ion-equilibria-and-solubility/
{complexions.solubility.JPG}

Possible approach
Solubility product expressions
What happens when something dissolves?
http://www.youtube.com/watch?v=xdedxfhcpWo
http://nobel.scas.bcit.ca/chem0010/unit9/9.4_solubilityionic.htm
also
http://www.chem.ufl.edu/~itl/2045/react/dissolution_of_cmpds.swf animation of NaCl idssolving.
Get students to dissolve some NaCl and calcium hydroxide in two separate beakers of water. Stir chemicals to dissolve. Ask students what the difference is and lead them to the idea that the NaCl is soluble but the calcium hydroxide isn't. Revise the fact that calcium hydroxide solution is limewater. Get students to filter the calcium hydroxide mixture and and then bubble Carbon dioxide into it. Filtrate should go milky i.e. the filtrate was limewater and so a small amount of calcium hydroxide had dissolved in the water even though the compound seemed to be insoluble. This leads to the idea that even compounds that to our eyes are insoluble are in fact slightly soluble i.e. they are sparingly soluble.
Revise molar ratios.
Develop solubility product constant expressions for the compound types mentioned in the SLOs
Pages 247- 252 in the 2006 edition of "Year 13 Chemistry NCEA level 3" practical workbook by Cooper and Abbott has exercises that revise equilibria and then introduce students to writing equilibrium constant expressions. Be aware of copyright considerations.
http://www.youtube.com/watch?v=FsU8Ss6jiKs&safe=active
"Continuing Chemistry" page 165 (2013 addition)
University Bursary and Scholarship Chemistry" page 141 (see page 148 for the derivation of the two expressions)
the 2006 edition of "Year 13 Chemistry NCEA Level 3 Practical Workbook pages 247 - 254 (Cooper and Abbott) has some exercises that will test student ideas -be aware of copyright considerations.
Predicting precipitation -the ionic product
page 168 (power points included in the CD that goes with the book)
http://learn.burnside.school.nz/course/view.php?id=854 is the link to AS 3.6 Moodle version in"Continuing Chemistry"
"University Bursary and Scholarship Chemistry" page 152
http://www.youtube.com/watch?v=jpXF93w5Dys Ionic product discussion and worked examples
After this clip it will probably be necessary to emphasise the fact that the only source of silver ions is from the silver iodide and so its value represents the concentration of silver iodide in a solution that contains iodide ions from another source.
Lots of practice with problems is necessary.
Complex ions and solubility
e.g.
from:
https://www.boundless.com/chemistry/acid-base-equilibria/complex-ion-equilibria-and-solubility/complex-ion-equilibria-and-solubility/
{complexions.solubility.JPG}
So the silver chloride is removed as the silver complexes with ammonia.
The effects of adding and acid to sparingly soluble salt with a basic anion
http://chemed.chem.wisc.edu/chempaths/GenChem-Textbook/The-Solubilities-of-Salts-of-Weak-Acids-977.html
Acid-Base Stuff