Friday, April 27, 2007
Fri-Day 2 and AP Review Instructions
Regents: thanks to Anthony G., who found an error in the answer key (!), the class average on the last test went up two points to an 81! Good eye!
Today, we discussed characteristics of acids and introduced the conceptual Arrhenius and Bronsted definitions of acids.
I'll assign some reading for this unit over the weekend.
Honors: we finished our discussion on delta G, entropy, and enthalpy. We did several examples in which we predicted the temperature at which a process or reaction becomes spontaneous.
We began our acid-base-salt unit by looking at characteristics of acids and see what happens when a strong or weak acid is dissolved in water.
I'll assign some reading for this unit over the weekend.
AP: we wrapped the Nuclear unit noting the correct conversion factor in Einstein's equation. If the mass defect is calculated in amu, you must convert that to kg by multiplying by
1.66 x 10^-27 kg per amu. Then, plug the mass defect in for delta m in E = delta m c^2 . This energy is the nuclear binding energy. Finally, to get the binding energy per nucleon, divide by the mass of the isotope's nucleus (in kg or amu). Fe-56 has the highest binding energy per nucleon and the greatest mass defect per nucleon.
We then looked at useful radioisotopes including C-14 (important in carbon dating and in elucidating biochemical pathways), U-238 (its ratio to its 14-step decay series stable product, Pb-206 in a rock sample determines the age of crazy old rocks/the Earth), and others.
We then began a part I section of the 1989 exam. The exams begin with some quick-start questions. It is crucial not to rush through these; these questions are simple enough that you will naturally do them quickly even if you are meticulous and careful (underlining keywords, DRAWING examples, diagrams, definitions, etc.). Start the test strong and accurately; later on, you will have to INITIALLY pass on a few weed-out questions that are DESIGNED TO CONFUSE, FRUSTRATE, and decimate the average test-taker. SEE those questions for what they are and coolly sidestep them, initially.
When you complete this exam, this weekend, do so under TIMED conditions! We spent about 15 minutes on the exam so try to finish the rest of the test in 75 minutes. If there are questions remaining thereafter, answer them with a different color pen or a pencil. After that, show all work that you didn't have time to explicitly show during the timed portion so that you can reinforce the reasoning involved in answering these questions. Email me if you are flummoxed by a given question (remember that sketchy CaCO3 vs. BaSO4 question).
Good luck. I will post Monday's part II exam for preview.
Clear your calendar for next Saturday, AP Exam trial day. You will be taking the entire 2002 AP Chem exam under timed conditions in the Board Room. On that day, you will see clearly where you stand in your quest for a 5. I cannot overemphasize the importance of being in that Board Room next Saturday morning at 10AM with your classmates and taking that test as the real deal. The test takes 90 minutes for Part I; then we take a ten-minute break followed by a 90-minute part II (40 minutes with a calculator, 50 minutes without a calculator). I grade the part I's while you all take the part II so we can generally finish grading and analysis in 45 minutes. Then, you'll have your AP score! Of course, don't ruin this simulation by even accidentally looking at the 2002 exam beforehand. The test does not in any way shape or form count towards your course average. It is simply the best diagnostic tool to show you how to focus your last ten days of study before the 2007 AP exam.
Fortunately, this year, we have a little more time for review so, wherever you may have a weakness on that official test, you have time for improvement. I will hold an optional timed exam the following weekend (either way, I will give you a copy of that exam).
Today, we discussed characteristics of acids and introduced the conceptual Arrhenius and Bronsted definitions of acids.
I'll assign some reading for this unit over the weekend.
Honors: we finished our discussion on delta G, entropy, and enthalpy. We did several examples in which we predicted the temperature at which a process or reaction becomes spontaneous.
We began our acid-base-salt unit by looking at characteristics of acids and see what happens when a strong or weak acid is dissolved in water.
I'll assign some reading for this unit over the weekend.
AP: we wrapped the Nuclear unit noting the correct conversion factor in Einstein's equation. If the mass defect is calculated in amu, you must convert that to kg by multiplying by
1.66 x 10^-27 kg per amu. Then, plug the mass defect in for delta m in E = delta m c^2 . This energy is the nuclear binding energy. Finally, to get the binding energy per nucleon, divide by the mass of the isotope's nucleus (in kg or amu). Fe-56 has the highest binding energy per nucleon and the greatest mass defect per nucleon.
We then looked at useful radioisotopes including C-14 (important in carbon dating and in elucidating biochemical pathways), U-238 (its ratio to its 14-step decay series stable product, Pb-206 in a rock sample determines the age of crazy old rocks/the Earth), and others.
We then began a part I section of the 1989 exam. The exams begin with some quick-start questions. It is crucial not to rush through these; these questions are simple enough that you will naturally do them quickly even if you are meticulous and careful (underlining keywords, DRAWING examples, diagrams, definitions, etc.). Start the test strong and accurately; later on, you will have to INITIALLY pass on a few weed-out questions that are DESIGNED TO CONFUSE, FRUSTRATE, and decimate the average test-taker. SEE those questions for what they are and coolly sidestep them, initially.
When you complete this exam, this weekend, do so under TIMED conditions! We spent about 15 minutes on the exam so try to finish the rest of the test in 75 minutes. If there are questions remaining thereafter, answer them with a different color pen or a pencil. After that, show all work that you didn't have time to explicitly show during the timed portion so that you can reinforce the reasoning involved in answering these questions. Email me if you are flummoxed by a given question (remember that sketchy CaCO3 vs. BaSO4 question).
Good luck. I will post Monday's part II exam for preview.
Clear your calendar for next Saturday, AP Exam trial day. You will be taking the entire 2002 AP Chem exam under timed conditions in the Board Room. On that day, you will see clearly where you stand in your quest for a 5. I cannot overemphasize the importance of being in that Board Room next Saturday morning at 10AM with your classmates and taking that test as the real deal. The test takes 90 minutes for Part I; then we take a ten-minute break followed by a 90-minute part II (40 minutes with a calculator, 50 minutes without a calculator). I grade the part I's while you all take the part II so we can generally finish grading and analysis in 45 minutes. Then, you'll have your AP score! Of course, don't ruin this simulation by even accidentally looking at the 2002 exam beforehand. The test does not in any way shape or form count towards your course average. It is simply the best diagnostic tool to show you how to focus your last ten days of study before the 2007 AP exam.
Fortunately, this year, we have a little more time for review so, wherever you may have a weakness on that official test, you have time for improvement. I will hold an optional timed exam the following weekend (either way, I will give you a copy of that exam).
# posted by C @ 4:06 PM 
