Unit Exam

After taking the unit exam, I feel that I got a pretty good score. I was concerned with this test after the quiz but I prepared by doing a lot of practice problems. In the future, I will continue to use the practice exams to study!

Helpful Links
http://chemwiki.ucdavis.edu/Inorganic_Chemistry/Reactions_in_Aqueous_Solutions/Unique_Features_of_Aqueous_Solutions
http://www.chemteam.info/Solutions/Dilution.html
https://www.youtube.com/watch?v=5JvAkVgxI-0
http://www.chem.ucla.edu/~gchemlab/soln_conc_web.htm

Murder Mystery Lab

In this lab, we were given a mystery murder solution and suspects possessing various similar solutions. By determining the identity and molarity of the solution used for the murder, we can find the killer. To start, we found the precipitate of the solution when reacting with other chemicals to distinguish the identity of the solution. Then we weighed the precipitate and used stoichiometry to find the molarity.

Test reaction

Drying the precipitate

The precipitate

Dilution Lab

In the dilution lab, we diluted  a solution of water and food coloring by doing subsequent dilutions. This lab really helped me visualize serial dilutions and understand the concentrations.

Helpful Links:
http://www.quansysbio.com/dilutions
https://en.wikipedia.org/wiki/Serial_dilution
https://www.youtube.com/watch?v=HZzpgjGosmg

Copper(II) Chloride Lab

In this lab, we placed an iron nail in Copper(II) Chloride and used stoichiometry to determine whether Iron(II) Chloride or Iron(III) Chloride formed. I liked this lab because it helped me understand percent yield and how it relates to the theoretical yield. In the end, we had Iron(II) Chloride when comparing the percent yields.

Percent Yield

Usually, the amount of product actually produced in a reaction is less than the theoretical yield. To find the efficiency of a reaction, you can get a percent yield by comparing actual yield and theoretical yield.   Percent yield is the actual yield divided by the theoretical yield of a reaction multiplied by 100. Percent yield is pretty easy once you do some practice problems.

Helpful links
https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/mass-relationships-and-chemical-equations-3/reaction-stoichiometry-44/calculating-theoretical-and-percent-yield-234-4704/

https://www.khanacademy.org/science/chemistry/chemical-reactions-stoichiome/limiting-reagent-stoichiometry/a/limiting-reagents-and-percent-yield

Foundations of Stoichiometry

In this unit, we have learned how to use a balanced chemical equation and some given information to predict an amount of reactant or product. By picking out the given and end goal, you can compare then moles of each substance using coefficients from the balanced equation to get a theoretical answer. You can also use stoichiometry to find limiting reagents by looking at which reactant produces the least amount of product in a reaction.

Helpful links
http://chemwiki.ucdavis.edu/Analytical_Chemistry/Chemical_Reactions/Stoichiometry_and_Balancing_Reactions

https://www.khanacademy.org/science/chemistry/chemical-reactions-stoichiome/stoichiometry-ideal/v/stoichiometry

http://www.chemteam.info/Stoichiometry/What-is-Stoichiometry.html

www.tes.com

Stoichiometry Quiz

After taking the quiz yesterday, I felt like I did pretty well on it. Stoichiometry is easy to understand once you know your end goal and memorize the road map. As long as you also have a grasp on the material from other units like predicting the products of chemical reactions, you will not stress out over this unit. The notes and practice tests in this unit have also helped me a lot since stoichiometry becomes much more comfortable after a few practice problems.

Helpful links

http://www.chem4kids.com/files/react_stoichio.html

http://www.chemcollective.org/activities/tutorials/stoich/reaction_stoi