SciHawks

Thanks to all who came to extra help, and to the final AP Chem Practice exam;
between the hard work of solving problems and making corrections,
we had some Chipotle, 5 Guys, and did some "experiments":










Physics - finished up our Modern Physics by seeing the organization of the fundamental particles and sub-sub particles of matter - they all have crazy names but the main thing is to keep track of the charges and write out your own "anti-particle" chart.
We then discussed the four fundamental forces of nature: strong nuclear, weak nuclear, electrostatic, and gravitational. Of course the strong nuclear force is by far the strongest, BUT all nuclear forces only "work" or "exist" within the very very tiny nucleus, whereas the gravitational force is exerted over vast universal distances.
Our unit exam is on Monday and Tuesday.

Physics - we discussed the atom, its structure, and definitions of atomic mass, mass number (protons + neutrons), atomic number, etc.
We used these various terms to calculate the number of protons, electrons, and neutrons of a given isotope of an atom.
We then discussed nuclear FUSION, in which protons and neutrons bind together to form a nucleus.
In this process, some nuclear mass is lost and converted to energy, which is equal to the binding energy of the nucleus; in other words, the more nuclear mass lost, the more energy released, and the more tightly bound are the protons and neutrons in the nucleus.
Using Einstein's most famous equation, we calculate the nuclear binding energy or energy released via the fusion formation of a given nucleus, using the "mass defect" as the mass in E = mc2.

AP Chem - we saw two other uses of the Thermodynamic state function , H, enthalpy. We saw how to do a "Hess Law Diagram" in calculating the lattice energy of a salt; we also did problems in which bond enthalpies, i.e. bond dissociation energies are used to determine the delta H of a reaction. We just drew the structures, and all of the bonds, and then just added the bond dissociation energies (all positive) to the bond formation energies (the negative of the bond dissociation energies).
We also did the 1999 part I exam, the questions that we did not get to are for HW.

Physics - we did a Compton Effect review problem, and then we discussed the wave nature of matter as discovered by de Broglie (the wave interference pattern of electrons was observed).
We then discussed the momentum of photons, a consequence of the particle nature of light.

We then calculated the energy of a photon emitted for a given electron transition from a higher level of energy to a lower level of energy; we calculated the energy of a photon absorbed by an electron causing the electron to go to (have) a higher level of energy.

AP Chem - we did some of the questions from the 2010B AP Chem exam during which we discussed test psychology, organic chemistry, and some electrochemistry.

Kudos to all who made the effort to attend the two review sessions yesterday (outside!) and today, as well as the practice AP exam/pizza party.
By correcting your errors and getting some good test-taking experience (pacing, predicting correct answers, eliminating impossible answers), you are preparing to get a 5 on the AP exam, the final arbiter of your performance in this course.

We have one more chance to practice a full AP exam this Saturday morning in the Springer gym.
The exam will start at 9AM, and we will be done grading it by 1PM; your 2011 AP Chem exam will ensue 48 hours thereafter.

For those who have not taken advantage of these exams and review sessions, there is nothing to take advantage of AFTER the AP exam, so do not miss your final opportunity to gauge how well you will do on next Monday's exam.

Physics - we discussed the Compton Effect, further evidence that light/EMR (as well as ANY TYPE of energy) exists as separate particles of energy called photons (or quanta). When a stream of photons is fired at a stream of electrons, the particles collide and scatter. The photons lose energy, and the electrons gain/absorb energy from the photons during the collision. Energy and momentum is conserved so, measuring the wave components of the light, we measure that the frequency of the light decreased; using Planck's equation, we see that the energy of each photon diecreases.
We did problems of this type in the unit packet.
When we return, we will finish up this unit by looking at the "standard model" of all matter in the universe (everything is on the Reference Table, NOTHING needs to be memorized - the names are kind of crazy).
The unit test will be the following Monday/Tuesday - you must let me know if you have an AP exam either day, thank you.

AP Chem- we finished electrochem for Voltaic/spontaeous cells under standard Eo and non-standard (Nernst equation) conditions. We then did a typical electrolytic (nonspontaneous) cell calculation for electroplating. We briefly discussed nuclear decay and the 4 types of nuclear emanations, their causes, and balancing nuclear equations.
The Spring Break assignment was handed out and is posted.
PROJECT KARMA, your one and only opportunity to thoroughly prepare for the AP exam while improving your grade, was briefly described. I will send you and email detailing the requirements. Those who CORRECTLY did  this assignment in the past got a 5 on the AP Chem exam (okay, 1 out of dozens got a 4).
This should/will not be a vacation from AP Chem; there will be plenty of time to relax after May 2nd.
I will send an email regarding a review session this upcoming week, and the last day of the break- that night, I will proctor another official released test (by that time, I will have reviewed all of the first test at the review sessions) so that your 5 will be a deeper 5 or your 3 or 4 will turn into a 4 or 5.
Excelsior!

Thanks to all who went the marathon distance today, taking the 2002 AP Chemistry exam. You have a decent amount of time to improve upon today's performance, even those of you who clearly have a very safe 5 - you can always go for a "theoretical" 6 :)
I will give you all the opportunity to go over ANY and EVERY question that you got wrong or were not sure about.

I expected but at the same time I am impressed with the maturity and test-taking commitment that you showed; nobody staring into space instead of checking work, improving answers, etc. This bodes well for us.

The next proctored practice exam will be on Tuesday April 26 (6 days before your AP Chem exam), the last day of our break; the test will be in the current format.
If I can schedule an open room, I will even do a marathon review session before that, perhaps that Monday.
Most of you should be back from vacation by then, and we should go all out until May 2nd.

Cheers and Happy Vacation!

Physics - we discussed the origin of light and ALL electromagnetic radiation: all EMR, in the form of photons, separate individual packets of mass-less energy is engendered from the energy "lost" by an electron as it goes from farther from the nucleus (an excited state) to closer to the nucleus (a less excited state). Energy cannot be created or destroyed so the loss in potential energy of the electron takes the form of the energy of a photon, which is simultaneously emitted by the atom or ion.

We then calculated the energy of photons that formed from electron transitions, and then we associated these photon energies with the WAVE nature of the same EMR by using Planck's equation,
Ephoton = hf .
We then began to go over our comprehensive 3rd quarter exam.

AP Chem - took our Ksp solubility exam; people who "rehearsed" particular answers, and IGNORED what was actually being asked wrote a lot of IRRELEVANT information for NO CREDIT! This was a difficult unit, so to witness people cramming/reading notes at the last minute showed the fecklessness of such an approach to this course.

Physics - we did a review kinematics problem, and then we discussed the origin of light, which stems from the loss of energy of electrons as they move back towards the nucleus of an atom as a result of electrostatic attraction. We use the energy of the photons emitted to deduce the possible "LEVELS OF ENERGY" that an electron can have in a given atom.

AP Chemistry - as you study for tomorrow's Ksp equilibrium exam, do not worry about a Thermodynamics question. I will ask just the Ksp related questions from our unit notes and problem sets.

Physics- began our final new unit: Modern Physics.
In this unit, we qualitatively and quantitatively discuss and show the particle nature of light, as well as the wave nature of matter- two unintuitive aspects of these phenomena.
We reviewed the evidence for the wave nature of light, and then introduced Einstein's Photoelectric Effect experiment in which the PARTICLE nature of light is inferred.

AP Chem - did a Hess's Law problem, and then discussed the other factor that determines the spontaneity of a reaction: entropy.

Physics - we continued prep for the quarterly; check the remaining solutions on Blackboard.
Review your notes FIRST, and then do as many problems as possible before Thursday and Friday's quarterly- your final opportunity to replace a poor performance/effort - i.e. the test counts by itself AND it can also replace a lower grade.

AP Chem - did a part 1, the explanations to which must be written as your hw.
This is a longer exam so this hw will not be due until FRIDAY in class.

Physics- we began our quarterly review during our abbreviated period.

AP Chem - we reviewed our first part II exam; do whatever questions that we did not do in class and add that to the work from class; hand that in as your hw for tomorrow.
We will do a part 1 on Wednesday, see Blackboard.

Physics - we reviewed the multiple choice part of the Waves 2 exam.
We then finished up our index of refraction of water lab, seeing how the refracted ray that we traced to the ruler, actually bends towards the normal in the denser water (relative to air).

AP Chem - finished another selective precipitation problems, and then mapped our plan for this month:
each day, you will be given a part I or part II past AP Chem exam. Preview or take the exam the night before, within the time limits, of course.
In class the next day, we will do whatever questions that the majority want answered; the rest of the exam is the hw for that night, which is due the next day. This hw will have a significant impact on your fourth quarter grade, and is excellent preparation for the MONDAY, May 2nd AP Chemistry exam.
Between exam review, we will squeeze in the basics of our final two units.
DONE CORRECTLY AND WITH HONEST EFFORT, you can transform yourself, and achieve a confident 5 on the AP Chem exam.

Physics - took the written-response part of the Waves 2 exam

AP Chem - finished up our Ksp equilibrium unit.
We completely explained the increase in solubility of all salts with increasing hydronium ion concentration; the ONLY exceptions are salts of conjugate bases of 5 of the strong acids : chlorides, bromides, iodides, nitrates, and perchlorates.
We explained each of the parts of a selective precipitation problem, determining the concentration of ions from a less soluble salt that remains when the more soluble salt is just at the saturation/precipitation point.