Wednesday, March 24, 2010
Wednes-Day 2
Bio - check out Blackboard for two practice tests (with ANSWER KEYS) on Meiosis/gamete production and Sexual Reproduction/Development. Take these tests before Friday for a good reinforcement of the material. Email me and/or come to extra help if you cannot do one or more of the test questions.
Today we reviewed/focused on embryonic development from the fertilized egg in the oviduct to the implanted gastrula in the uterus (pregnancy) to the DIFFERENTIATION and specialization of the cells from each of the three layers of the gastrula. We then defined growth, aging, and death.
Tomorrow, we will do a cumulative unit activity that tests your understanding of the concepts/ideas from this unit. (...and we'll eat some gummy worms, if so desired).
AP Chem - we saw how to determine whether a given salt solution is slightly acidic or slightly basic given that BOTH of the salt's ions hydrolyze water; we simply use the Ka and Kb information given for the hydrolysis by these ions (sometimes, we must use the pKa and pKb of their CONJUGATES, which we saw in class).
We then showed how to calculate the effect on the concentrations of conjugate acids and bases in a buffer solution, when a strong acid or strong base is added; we also saw the effect of adding a strong acid to a non-buffer solution (much greater effect on the pH).
We saw the convenient bookkeeping method of using a SRFC Table, which we use whenever solution volume is changing. The most important thing to do in these problems is to DRAW OUT WHAT IS IN SOLUTION so that you can SEE what is reacting. You then set up your SRFC table based on the actual (limiting) reactant equation that you see. The results of your table either are plugged into the H-H equation (if still in the buffer 1/10 - 10/1 region) or put into an ICE table using either the hydrolysis of water by the conjugate base or by the conjugate acid, BOTH/EITHER will get you the same correct answer!
# posted by C @ 1:52 PM 
