Tuesday, May 17

Today, we started off class by picking our lab notebooks up from the back table and receiving our grades for the last 3 labs we completed + the new packets. Mr. Henderson announced that the test is on Homelogic as of this morning along with our labs. He told us that if we had any questions about the test to see him in the science office anytime this week in the *MORNING.* Mr. H then began to describe how the rest of the year was going to look like: we're only going to complete about half of the next two packets (1/2 units of ch. 13 & 14), there will be only 4-5 more labs, there will be a quiz for each chapter and quizlets throughout each, and most importantly - IN-SCHOOL FINAL REVIEW SESSIONS. Next Tuesday, Mr. H won't be here so he's going to give us the final exam, which is a standardized test consisting of about 80 multiple choice questions. We will have time to preview it in class and go over it the next day. However, the actual test will be a little different with about 5-6 additional written questions. He reminded us that we will be able to use our note cards once again for the exam. He also said that from this point on reading sheets are optional (but highly recommended). Subsequently, we began the new unit: Electrochemistry.

Essentially, the purpose of the unit is to understand how batteries work. We'll be making a battery out of FRUIT later this week (as a lab). We turned to page 1:
-there are 2 reaction types, acid-base and oxidation-reduction
-oxidation: the imaginary charge which an atom would have if the shared electrons among covalently bonded atoms were considered to be shared equally among bonded atoms.
Mr. H told us the definition (^^) was bad and just remember that it is a number. We used the tablet with "Rules for Assigning Oxidation Numbers" to do number 1A-1H. The answers-

We then turned to page 2:
-oxidation: an increase in oxidation number associated with a loss of electrons
-reduction: a decrease in oxidation number associated with a gain of electrons
-OIL RIG: Oxidation Is [electron] Loss, Reduction Is [electron] Loss
-LEO GIR: Loss Of [electrons] = Oxidation, Gain Of [electrons] = Reduction
-If one substance is losing electrons, another substance must gain the electrons.
-oxidizing agent: substance that is oxidized, gains electrons that are lost
-reducing agent: substance that is reduced, loses electrons
We used the concepts introduced on both pages to completer parts b and c. The answers-

Although there is no homework for points due tomorrow, there is that optional reading sheet.