Friday, December 2, 2011
Fri-Day 2
AP Chem - please thoroughly review your last test; only two students came to extra help to review their tests. Those who did poorly must compensate by studying more effectively, which entails finding out how to do so. I can show you how to study more efficiently and effectively at extra help.
Daily review and copying of notes is a starting point; doing the problems on the practice tests and worksheets, and submitting your answers BEFORE a test for constructive criticism or assessment, will prevent you from making many mistakes on the actual exams.
On this past exam, the following types of errors will not be repeated:
Treating an AP Chemistry exam as if it is a text chatroom; do NOT abbreviate any words or terms; for particularly long and highly repeated words or phrases, you may designate an acronym or abbreviation along with a KEY, after which you may use the acronym/abbreviation throughout that given question.
You absolutely MUST use the key terms/words DIRECTLY from the question within, and possibly throughout, your answer.
Write the general formula that you are using in solving an equation, with each variable labeled in DETAIL (e.g. energy PER PHOTON); of course you should either start with the variable that is being solved for ISOLATED on one side of the equation, so that your calculation and units cancel in ONE step.
If that is not possible, show the derivation of the formula that isolates the unknown variable, and then solve in one step showing all proper unit cancellation.
On multiple choice questions, SHOW YOUR WORK explicitly; NOT FOR ME, but for you. Have it register that many of the questions that you missed were due to your trying to juggle to much information in your head, when you could have instead written things out clearly so that you could SEE how to get the right answer.
Read what you wrote with any explanation and make sure that your answer is LOGICAL (in cause and effect order!), coherent, and that each line relates to the question asked.
The explanation/qualitative part of this course never ends; you must learn to understand and write proper explanations otherwise you will do very poorly for the rest of this course. This often requires much written practice and correction (from me, BEFORE a test).
Our exam on the Periodicity unit on Monday will cover, as usual, all notes from this unit; I will later post a list of possible question types:
Update: On this largely qualitative test, which gauges your understanding in logical order of CAUSE and EFFECT, you will be asked about the trends in the periodic table, as well as selected anomalies.
Here's a tip to help increase the quality and logic of your explanations:
as you write EACH LINE of an explanation, picture the test grader writing/saying, "YOU ARE WRONG; YOU ARE LYING, THE OPPOSITE IS TRUE", and THEN prove the grader/AP reader wrong by stating how and why that person is wrong by stating your evidence/ drawing/ showing your mechanism! This way, you are proving your case, making a thorough, sufficient argument for your explanation.
On tomorrow's exam, expect questions on:
- explanation of periodic trends down groups or (from left to right) across periods in order of increasing atomic number in terms of
1.Zeff on valence electrons,
2.# of OPEL's, and
3.degree of e- - e- repulsion among electrons in the valence or outermost shell.
- explanation of any given periodic anomaly (e.g. ionization energy, electron affinity); the anomaly will be GIVEN. Remember, you cannot predict anomalies, but they can be explained.
- explanation of successive ionization energies, and their relation to determining the number of valence electrons of an element
- explanation of relative sizes of a series of atoms and/or ions
- explanation of the increasingly endothermic successive electron affinity
- general differences between metals and non-metals
- knowledge of the approximate/exact electronegativity values of the 11 non-metals
- predict the products of our known chemical reaction types (anionic/cationic single replacement, double replacement with precipitation, etc.); for anionic and cationic single replacements, that means knowing the relative reactivities of the metals (any metal is more reactive than the four "noble metals", Cu, Ag, Au, and Pt), and of the nonmetals (fluorine is the most reactive, etc.).
Bio - we discussed the two types of anaerobic cellular respiration, each of which extracts merely enough energy from glucose to form 2 ATP molecules. Organisms that can perform only anaerobic respiration are necessarily limited in their energy extraction/production so they are also limited in growth/size (this is why there are no anaerobic organimsms larger than a bacterium).
We showed the two possible anaerobic pathways: alcoholic fermentation in which ethanol alcohol and carbon dioxide are produced from glucose, and lactic acid fermentation, which produces lactic acid from glucose.
Daily review and copying of notes is a starting point; doing the problems on the practice tests and worksheets, and submitting your answers BEFORE a test for constructive criticism or assessment, will prevent you from making many mistakes on the actual exams.
On this past exam, the following types of errors will not be repeated:
Treating an AP Chemistry exam as if it is a text chatroom; do NOT abbreviate any words or terms; for particularly long and highly repeated words or phrases, you may designate an acronym or abbreviation along with a KEY, after which you may use the acronym/abbreviation throughout that given question.
You absolutely MUST use the key terms/words DIRECTLY from the question within, and possibly throughout, your answer.
Write the general formula that you are using in solving an equation, with each variable labeled in DETAIL (e.g. energy PER PHOTON); of course you should either start with the variable that is being solved for ISOLATED on one side of the equation, so that your calculation and units cancel in ONE step.
If that is not possible, show the derivation of the formula that isolates the unknown variable, and then solve in one step showing all proper unit cancellation.
On multiple choice questions, SHOW YOUR WORK explicitly; NOT FOR ME, but for you. Have it register that many of the questions that you missed were due to your trying to juggle to much information in your head, when you could have instead written things out clearly so that you could SEE how to get the right answer.
Read what you wrote with any explanation and make sure that your answer is LOGICAL (in cause and effect order!), coherent, and that each line relates to the question asked.
The explanation/qualitative part of this course never ends; you must learn to understand and write proper explanations otherwise you will do very poorly for the rest of this course. This often requires much written practice and correction (from me, BEFORE a test).
Our exam on the Periodicity unit on Monday will cover, as usual, all notes from this unit; I will later post a list of possible question types:
Update: On this largely qualitative test, which gauges your understanding in logical order of CAUSE and EFFECT, you will be asked about the trends in the periodic table, as well as selected anomalies.
Here's a tip to help increase the quality and logic of your explanations:
as you write EACH LINE of an explanation, picture the test grader writing/saying, "YOU ARE WRONG; YOU ARE LYING, THE OPPOSITE IS TRUE", and THEN prove the grader/AP reader wrong by stating how and why that person is wrong by stating your evidence/ drawing/ showing your mechanism! This way, you are proving your case, making a thorough, sufficient argument for your explanation.
Try it!
Also, you should BEGIN YOUR EXPLANATION with a COMPLETE DRAWING AND/OR DIAGRAM that is LABELED and REFERENCED (simply by drawing ARROWS TO THE DRAWINGS OR DIAGRAMS) throughout the explanation.On tomorrow's exam, expect questions on:
- explanation of periodic trends down groups or (from left to right) across periods in order of increasing atomic number in terms of
1.Zeff on valence electrons,
2.# of OPEL's, and
3.degree of e- - e- repulsion among electrons in the valence or outermost shell.
- explanation of any given periodic anomaly (e.g. ionization energy, electron affinity); the anomaly will be GIVEN. Remember, you cannot predict anomalies, but they can be explained.
- explanation of successive ionization energies, and their relation to determining the number of valence electrons of an element
- explanation of relative sizes of a series of atoms and/or ions
- explanation of the increasingly endothermic successive electron affinity
- general differences between metals and non-metals
- knowledge of the approximate/exact electronegativity values of the 11 non-metals
- predict the products of our known chemical reaction types (anionic/cationic single replacement, double replacement with precipitation, etc.); for anionic and cationic single replacements, that means knowing the relative reactivities of the metals (any metal is more reactive than the four "noble metals", Cu, Ag, Au, and Pt), and of the nonmetals (fluorine is the most reactive, etc.).
Bio - we discussed the two types of anaerobic cellular respiration, each of which extracts merely enough energy from glucose to form 2 ATP molecules. Organisms that can perform only anaerobic respiration are necessarily limited in their energy extraction/production so they are also limited in growth/size (this is why there are no anaerobic organimsms larger than a bacterium).
We showed the two possible anaerobic pathways: alcoholic fermentation in which ethanol alcohol and carbon dioxide are produced from glucose, and lactic acid fermentation, which produces lactic acid from glucose.
# posted by C @ 3:16 PM 
