Tuesday, May 01, 2007
Tues-Day 4
Honors: we covered reactions of Bronsted bases and further practiced with conjugate acid base pairs. We defined acids (electron pair acceptors) and bases (electron pair donors) according to the Lewis Concept. We continued with Bronsted conjugate acid-base pairs and predicted, based on acid and base strength, whether the products or the reactants are favored at equilibrium. We reasoned that, the stronger a given conjugate acid, the weaker its conjugate base and vice-versa. The net or favored direction of a given reaction is from the STRONGER acid and base to the WEAKER acid and base.
Regents: we reinforced our definition of a Bronsted base (H+ acceptor) by doing several examples; we determined conjugate acid base pairs in reactions.We continued with Bronsted conjugate acid-base pairs and predicted, based on acid and base strength, whether the products or the reactants are favored at equilibrium. We also reasoned that, the stronger a given conjugate acid, the weaker its conjugate base and vice versa. The net or favored direction of a given reaction is from the STRONGER acid and base to the WEAKER acid and base.
AP: we briefly discussed the standard entropies of aqueous ions, which are the only entropy values that are relative; the "zero" entropy is for an aqueous H+ ion.
We also discussed that, given rate law information, only adding a reactant that is in the RATE determining step (i.e. the reactant is IN the rate law expression) can increase the rate of a reaction (other than increasing the temperature). Without such information, just stick with the usual kinetics/collision theory explanation.
We covered descriptive chem, another qualitative lab question that spanned acid-base, colligative property, AND redox questions. That is a good AP question.
We also did the sparingly soluble salt equilibrium question.
If you are shaky or unsure about any of these questions, you MUST GO TO YOUR NOTES FIRST! We have done all of these question types IN DEPTH and in many permutations. AFTER you carefully read the relevant notes, you should be able to do any of these questions. If you cannot, see me at extra help or email me. I want you to be confident and methodical on test day.
Regents: we reinforced our definition of a Bronsted base (H+ acceptor) by doing several examples; we determined conjugate acid base pairs in reactions.We continued with Bronsted conjugate acid-base pairs and predicted, based on acid and base strength, whether the products or the reactants are favored at equilibrium. We also reasoned that, the stronger a given conjugate acid, the weaker its conjugate base and vice versa. The net or favored direction of a given reaction is from the STRONGER acid and base to the WEAKER acid and base.
AP: we briefly discussed the standard entropies of aqueous ions, which are the only entropy values that are relative; the "zero" entropy is for an aqueous H+ ion.
We also discussed that, given rate law information, only adding a reactant that is in the RATE determining step (i.e. the reactant is IN the rate law expression) can increase the rate of a reaction (other than increasing the temperature). Without such information, just stick with the usual kinetics/collision theory explanation.
We covered descriptive chem, another qualitative lab question that spanned acid-base, colligative property, AND redox questions. That is a good AP question.
We also did the sparingly soluble salt equilibrium question.
If you are shaky or unsure about any of these questions, you MUST GO TO YOUR NOTES FIRST! We have done all of these question types IN DEPTH and in many permutations. AFTER you carefully read the relevant notes, you should be able to do any of these questions. If you cannot, see me at extra help or email me. I want you to be confident and methodical on test day.
# posted by C @ 9:36 AM 
