Friday, September 24, 2010
Fri-Day 2
Physics - Unit 1 test grades will be posted on Blackboard after 9PM (or a wee bit later).
We went over a couple of multiple choice question and found an answer key error- that boosted the class average by 5% :) Most students got 2 or 3 wrong out of the 20 multiple choice questions - pretty good overall.
We showed the difference between speed and velocity. We discussed the basic motion formulas involving time, distance, speed, and acceleration.
We tried to get a feel for the formulas and a sense of their meaning, particularly the formula for acceleration. We noted that any change in a variable is the difference between the FINAL quantity minus the INITIAL quantity.
We will do problem solving and graphical analysis. We will also collect and analyze lab data to see the relationships in the motion formulas.
AP Chem - now posted on Blackboard is the update data and solution to the para-cresol combustion analysis problem.
We did a percent composition to formula of a hydrated salt, noting that this time the mole ratios of formula units of the salt to molecules of water are the COEFFICIENTS in the formula. The (unwritten) coefficient of the salt part of the formula is almost always "1".
We then did a combustion analysis problem. Be sure to use an excess of significant figures in each step so that rounding errors are not multiplied throughout (this could lead to a wrong answer).
We then did a gravimetric analysis problem in which an unknown sulfate salt of known empirical formula is reacted/precipitated for the sulfate. Using the "gram method" or the "mole method", the unknown cation can be identified.
We went through the process of determining the empirical formula and molecular formula of a compound via combustion analysis.
Our unit exam is on Thursday. On Blackboard, there are many problems and tutorials with which to get additional practice. (Do NOT do the limiting reactant or percent yield problems yet; they are not on the test).
We went over a couple of multiple choice question and found an answer key error- that boosted the class average by 5% :) Most students got 2 or 3 wrong out of the 20 multiple choice questions - pretty good overall.
We showed the difference between speed and velocity. We discussed the basic motion formulas involving time, distance, speed, and acceleration.
We tried to get a feel for the formulas and a sense of their meaning, particularly the formula for acceleration. We noted that any change in a variable is the difference between the FINAL quantity minus the INITIAL quantity.
We will do problem solving and graphical analysis. We will also collect and analyze lab data to see the relationships in the motion formulas.
AP Chem - now posted on Blackboard is the update data and solution to the para-cresol combustion analysis problem.
We did a percent composition to formula of a hydrated salt, noting that this time the mole ratios of formula units of the salt to molecules of water are the COEFFICIENTS in the formula. The (unwritten) coefficient of the salt part of the formula is almost always "1".
We then did a combustion analysis problem. Be sure to use an excess of significant figures in each step so that rounding errors are not multiplied throughout (this could lead to a wrong answer).
We then did a gravimetric analysis problem in which an unknown sulfate salt of known empirical formula is reacted/precipitated for the sulfate. Using the "gram method" or the "mole method", the unknown cation can be identified.
We went through the process of determining the empirical formula and molecular formula of a compound via combustion analysis.
Our unit exam is on Thursday. On Blackboard, there are many problems and tutorials with which to get additional practice. (Do NOT do the limiting reactant or percent yield problems yet; they are not on the test).
# posted by C @ 10:01 PM 
