Test overview

We took our stoichiometry unit exam today in class. Although the questions were difficult, they were relatively similar to the ones form the quiz, just a little more complicated. The one thing that was confusing to me was how there was a choice on each one that was "none of the above." This made it so if you did get an answer, but it was not a choice, you did not know if it was completely wrong or the answer just wasn't present.

Because of the tough multiple choice layout of the test, here is a link to a website giving tips for multiple choice test taking: https://www.socialpsychology.org/testtips.htm


Another problem with this test was the time it took to complete the problems. Because there was so much work involved and a lot of room for simple mistakes, you had to take your time; yet you had to make sure not to waste any either. Here is a link to a video, providing you with a quicker alternate way to solve stoich problems: https://youtu.be/FtzDgMbuC8M

Quiz

Last week we took a quiz over stoichiometry. Throughout the lessons we learned a few different things but they all focused on using the stoic method. There are two different ways that you can solve these equations. In one of the ways you transfer straight to moles and then compare the amount of moles that were made. In the second way, you go all the way to grams… which just adds an extra step to the equation but takes off more work at the end.

Here is a link to a video explaining these methods a little more in-depth: https://www.khanacademy.org/science/chemistry/chemical-reactions-stoichiome/stoichiometry-ideal/v/stoichiometry

Here is a map with the necessary info in order to complete a stoichiometry problem:

Copper (II) Chloride and iron lab part 2

Today in class we finalized our lab and calculated which iron chloride compound we had in our experiment. By calculating the actual yield of the copper as well as the percent yield of it using both FeCl2 and FeCl3, we could then figure out their percent yields. When we used our numbers we were able to figure out that FeCl3 was used in our experiment because the percent yield of FeCl2 was over 100%.

Here is a link describing the difference between actual and theoretical yield: http://www.science.uwaterloo.ca/~cchieh/cact/c120/yields.html

Here is a picture of our data:

Copper (II) Chloride and Iron Lab

Today in class we completed a lab where we dissolved Copper (II) chloride in water and then placed a nail in the solution. In doing this we completed the balanced equations and stoichiometry in order to figure out the theoretical yield. In a few days we will be able to calculate the actual yield in order to decide whether we were using Iron with a 2+ or Iron with a 3+ charge. Then, we will calculate the % yield using our results.


Here is a picture of me and my partner's lab:

Here is an image of what the ending copper is going to look similar to:

Here is a link to a video of the lab that we completed done by other students: https://youtu.be/xob2_6qhy9c

Here is a link to a website explaining percent yield:
 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/