Week of 9/16

Monday: Test day! Covered basic chem, mole problems, mass spec, chemical formula determination and naming.

Tuesday: Solutions intro.  We started with some mole of ions problems from this worksheet. Then we talked about how dissolving happens, the ambiguity of the physical/chemical change.   We also talked about electrolytes and that molecular compounds make non-electrolytes because they do not dissociate!   No homework – just make sure you can do molarity problems! Here’s the notes from today. Also look at this animation of salt dissolving.

Wednesday: I had lots of stuff planned for Wednesday, but we only managed to talk about and do problems on molarity and dilutions.  This took a bit longer than I thought because we needed to review old stuff in addition to helping you grapple with the situation of multiple solutes.

Thursday: We reviewed naming as it became very clear that many of you are struggling with this.  This led into naming acids and then into acid base reactions, net ionic, complete ionic, etc.  This was a short day – about 20 minutes less than usual.  Handed out acid naming packet.

Homework: Watch Percent yield and double displacement reaction videos

Friday: We went over some solubility rules and then wrote precipitation reactions, including net ionic reactions.  Handed out double displacement packet.  Important points:

  • Balance the ionic compound formulas using charges first! Then balance the equation.  If you find it difficult to balance a reaction it is probably because your formulas are wrong.
  • When showing pictures of a a reaction at the molecular level, make it clear which ions are floating around in solution and which are bonded (forming the precipitate).

By Monday you should have all of the textbook problems done.