Chemblog!

The class average on the Acid Base Buffer test was 119 out of 150 (about 80%). This is because the students who get 100s are being countered by those who get 60s. This disparity is primarily due to effort versus lack thereof. By now, you should know that one day of extra help the afternoon before day 4 (or NO extra help when it is clearly warranted!) is grossly inadequate preparation for a college level exam. Try that when you are in college (and the difficulty level will be about the same...harder as you go on unless you major in something that requires NO academic ability: sociology or education) and you will waste tens of thousands of dollars in tuition and, more importantly, an opportunity to become educated.
Furthermore, when I take the time to review a test in class, have the courtesy and sense to LISTEN AND MAKE CORRECTIONS ON YOUR TEST. You're going to have to make them anyway when you correct all of your tests sometime before the end of Easter break.
Speaking of corrections: be scrupulously clear and explicit with every correction; have the question written and then your answer with all units, sig figs, and complete sentences; leave NOTHING to chance or ambiguity. If you do not write these corrections in such a way that you are learning from and understanding your prior errors, you will receive no credit for your response and you will likely fail. Previous sig fig deductions do not have to be addressed but all corrected answers that are turned in must have the appropriate sig figs. If you lost a minor point on a long answer, address that point directly as your correction - state why it is wrong and also what is the correct answer.
As for the Buffer Test:
Acid Strength- BOND POLARITY is the PREDOMINANT factor for every trend except down a group of haloacids or chalco-acids (group 16 binary acids) in which case BOND STRENGTH (lack thereof, really) predominates.
Oxoacids: the acidic H is NOT bonded to a halogen or anything else in the oxoacid except an oxygen! The other stuff withdraws electron density from the H in the O-H bond. WHY AM I WRITING THIS?! ALL OF THIS IS DIRECTLY IN THE NOTES!
On buffer problems, you ALWAYS have some conjugate acid and base in solution otherwise it wouldn't be a buffer. Therefore, in the S line of the SRFC table, you will have a certain number mmol of BOTH substances. That usually leads to a ratio of concentrations of conjugate acid and base in the buffer range of .1 is less than [A-]/[HA] is less than 10.
--end of rant-- (passes out.)