Tuesday, March 15, 2005
Honors Test Analysis and Rant
Here are the results of our last Math of Chem Exam: B and D period each averaged 89. E Period had an 80 average. Even if I exclude the E period grades of the students who do not study or take this course seriously (it is obvious so don't bother to comment. Own your mistakes; just try to change), the average was 86.
So, the vast majority of you are doing very well. That means, whether you want to admit it or not, you know a lot more about chemistry and test-taking than most people thanks to your hard work.
Let's continue to learn from our errors that were made on this test, though. DO NOT do the following on any future test:
1. When you check your final answers, make sure that they do NOT have MORE significant figures than the "cheapest" numerical value in the question.
2. NEVER EVER use Celsius temperatures in any gas law equation.
3. If you EVER balance an equation as part of a stoichiometry question, USE IT !!!! You will need to use the mole ratios among the reactants and/or products later in the problem.
4. Table E, plain and simple: insoluble salts (i) form DILUTE saturated solutions; soluble salts (s) form CONCENTRATED saturated solutions.
5. EXACTLY the mistake I warned about REPEATEDLY!: when you do a solubility curve problem that is NOT in 100 g of water, YOU MUST SCALE IT UP OR DOWN APPROPRIATELY!
6. Mole fractions and ppm: FOUR WORDS: part divided by WHOLE!
7. Some people forgot the gas law formulas. They did not use the practical advice of 1. looking at the formulas two seconds before the test begins and 2. IMMEDIATELY WRITING THEM DOWN!!! Do that on every test from now on. It isn't cheating if you are not looking at a formula sheet during the test.
So, the vast majority of you are doing very well. That means, whether you want to admit it or not, you know a lot more about chemistry and test-taking than most people thanks to your hard work.
Let's continue to learn from our errors that were made on this test, though. DO NOT do the following on any future test:
1. When you check your final answers, make sure that they do NOT have MORE significant figures than the "cheapest" numerical value in the question.
2. NEVER EVER use Celsius temperatures in any gas law equation.
3. If you EVER balance an equation as part of a stoichiometry question, USE IT !!!! You will need to use the mole ratios among the reactants and/or products later in the problem.
4. Table E, plain and simple: insoluble salts (i) form DILUTE saturated solutions; soluble salts (s) form CONCENTRATED saturated solutions.
5. EXACTLY the mistake I warned about REPEATEDLY!: when you do a solubility curve problem that is NOT in 100 g of water, YOU MUST SCALE IT UP OR DOWN APPROPRIATELY!
6. Mole fractions and ppm: FOUR WORDS: part divided by WHOLE!
7. Some people forgot the gas law formulas. They did not use the practical advice of 1. looking at the formulas two seconds before the test begins and 2. IMMEDIATELY WRITING THEM DOWN!!! Do that on every test from now on. It isn't cheating if you are not looking at a formula sheet during the test.
# posted by C @ 7:52 PM 
