Chemical Composition Test

Today we took the post test for the chemical composition unit. I would say that this was the hardest test yet in this class. I worked for the whole class period and had rework many questions to double check them. Many problems were about application and some had multiple questions to them. In the end, I guessed on the last few questions as I ran out of time. Since I will need to study this later on, here are some helpful links.

http://www.ck12.org/book/CK-12-Chemistry-Concepts-Intermediate/section/10.9/

https://www.chem.tamu.edu/class/majors/tutorialnotefiles/empirical.htm

http://www.chemteam.info/Mole/EmpiricalFormula.html

http://www.chemteam.info/Mole/Emp-formula-given-mass-data.html

Mole Conversions

The mole is a standard unit of measurement in chemistry. It is defined as 6.02 * 10²³ Avogadro's number) atoms or molecules of a substance. Along with molar mass, these values can be used as conversion factors to find the amount of particles or the mass of a sample. This road map explains all the conversions

lrrpublic.cli.det.nsw.edu.au

www.ck12.org

Helpful Links:

http://chemwiki.ucdavis.edu/Physical_Chemistry/Atomic_Theory/The_Mole_and_Avogadro's_Constant

http://www.ck12.org/book/CK-12-Chemistry-Concepts-Intermediate/section/10.9/

http://www.chemteam.info/Mole/Avogadro-Number-CalcsII.html

Formula of a Hydrate Lab

In this lab we determined the formula of a hydrate by heating the hydrate in a test tube. We measured the water driven off by heat and the anhydrous compound left to get the formula. Some groups didn't pass the pre-lab quiz so not all of the class got into the lab. Fortunately, me and my partner both got our questions right. I think this is the best lab we've done so far because we got to use the bunsen burner.

Heating the hydrate and driving off the water

The end anhydrous compound with no water

Measuring the compound

Chemical Composition Pre Test

Yesterday we took the pre-test for this new unit. After I saw that the questions involved lots of math, I started guessing after attempting the first few questions. This unit will probably include lots of work. It will also require lots of math and I don't know if that will make this unit easier or harder. Chemical composition seems pretty hard so I hope I get through this unit!

www.lohninger.com