Stoichiometry Test

Surprisingly, I thought the Stoichiometry test was pretty easy. I prepared a lot more than usual last night, which I think helped me out on the test today, especially doing the exam tickler practice that was available to me. However, I thought the last test was pretty easy and I did not do so well, so I'm still nervous as I await the results of this test. Anyways, the semester is pretty much over. I feel that I did a pretty good job in this class over the semester, but there's always room for improvement. I've heard that second semester is a lot harder than first, so I'll have to put a lot more time and effort into this class next semester, but I think I will be able to do fine.

http://www.protrainings.com/why_us/flexible

Iron Lab

The Iron Lab was a very interesting lab. First, we put a polished iron nail in a solution of water and Copper(II) Chloride in a baby food jar. Then, we let it sit overnight in order to let the entire reaction take place. The next day, we took out the nail and washed all of the copper off of it. Next, we drained the excess fluid from the jar of copper, then washed it with water. We repeated the draining process, then washed the copper again with HCl, and we drained it once again. then, we shook the jar a little bit in order to allow the solution to dry easier. We let the copper dry over the weekend, then took the mass of it today. The purpose of the experiment was to determine the theoretical and actual yield of Copper, and then to determine the percent yield of the Copper. This was a really cool lab!

https://en.wikipedia.org/wiki/Metallurgy_during_the_Copper_Age_in_Europe

Helpful Links:

Theoretical Yield

Theoretical Yield Video

Stoichiometry Weekly Quiz

The stoichiometry quiz was fairly easy in my opinion. It was mostly a lot of the basic information, so it wasn't very tricky. Although I got a 90% on the quiz, I'm not too worried about the test. I need to continue to do practice problems and remember all of the rules. Also, I need to work on the percent yield problems for the test because I missed the lecture over the percent yield portion of this chapter. I need to do well on this test, so I am going to have to work hard to get the grade that I desire!

http://www.samfunnetiaas.no/en/quiz/

Helpful Links:

Percent Yield Explanation

Percent Yield Video

Stoichiometry Intro

Unfortunately, there wasn't a pretest for this unit. I actually like taking pretests because they help me see what's going to be on the unit before it usually starts. The pre tests also have some of the same questions as the post test so it is beneficial to me. Anyways, the first stoichiometry lecture was pretty easy. Most of it consists of conversions. You have to convert the initial mass to moles, then compare that the the moles of the other substance, and finally change that to grams in order to solve the problem. Hopefully the rest of the unit is as easy as this part!

https://www.tes.com/lessons/Dd1iN2u2z62JUQ/stoichiometry

Helpful Links:

Stoichiometry Video

Stoichiometry Help

Chemical Reactions Test

The chemical reactions test was fairly easy for me. I spent a lot of time last night looking over my notes and doing practice problems, which really benefited me, as there were many similar questions on the practice and on the test. The test was over all types of reactions, driving forces, solubility rules, oxidation numbers, the reactivity series and a few other topics. For the most part, the questions were easy, but there were a few hard questions for me, as I had not seen questions like that before. However, I think I successfully worked my way through the harder questions, and I think that I achieved an A on this test.

http://science.pppst.com/chemicalreactions.html

Helpful Links:

Chemical reactions Video

Chemical Reaction Metals Lab

In the Metals Lab, we combined different metals with aqueous solutions in order to see if the chemicals reacted. The main purpose of the lab was to demonstrate Redox reactions, as that is what we have been learning in class. Also, we created our own reactivity series based on the results of which elements reacted most often. In our experiment, Calcium was at the top of the reactivity series, for it reacted with every chemical that it was placed in, meaning that it had the highest probability of reacting with other elements. Lead, however, reacted with none of the chemicals it was placed in, so it was placed at the bottom of our reactivity series. This lab was fun to complete, for the reactions that we saw were interesting to see.

http://www.kgs.ku.edu/Hydro/GWtutor/Plume_Busters/remediate_refs/redox_chemistry.htm

Helpful Links:

Redox Reaction Help

Activity Series Help

Weekly Quiz for Chemical Reactions Unit

The weekly quiz that we took yesterday was fairly easy. The material contained questions about driving forces, chemical equations, balancing equations, and solubility rules. The quiz was not very difficult, yet it was kinda confusing. It took me a minute to understand what I was being asked, so I had a difficult time processing the quiz at first. Also, there were a couple questions that I was unsure about, so I just had to guess on them. The quiz was only 11 questions, so missing a few will not have a huge effect on my grade.

Solubility Lab

The solubility lab was very interesting. We mixed a variety of different chemicals in order to reinforce our knowledge of the solubility rules as well as driving forces in reaction. All of the chemicals started aqueous, and some of them formed a precipitate when they were mixed together. Overall, I think that more of our chemicals did not produce a driving force, meaning the new chemicals made were aqueous. The formation of a precipitate resulted from the production of a solid chemical when the double replacement reaction took place. The lab taught me a lot about the solubility rules, and helped me on my quiz.

Helpful Links:
List of Solubility Rules

Chemical Reactions Pre Test

Unfortunately, there was no Pre Test for the chemical reactions unit. Usually, the pre tests just make me feel really dumb anyways, so I'm kind of glad that there wasn't a pre test for this unit. Instead of the pre test, we went straight into notes, where we learned about different driving forces of reactions and the parts of writing chemical equations. Also, we learned how to balance normal chemical reactions as well as combustion reactions.

Helpful Links:
Balancing Equations Video
Driving Forces Video

Formula of a Chloride Lab

Yesterday in class, we did the Formula of a Chloride Lab. To complete the lab, we put a small piece of Zinc in a beaker, then added Hydrochloric acid. Next, we put the beaker on a hot plate, and heated the chemicals. The Zinc dissolved into the Hydrochloric acid, then water began to be driven off. We heated the mixture until there was no liquid left, and there was a salt left in the beaker. Then, we cooled the beaker and took it's mass. The purpose of the lab was to determine the empirical formula formula for the salt at the end of the lab. In our results, we got a ratio of one Zinc to 2.068 Chlorine, which was a 3% error, as the real ratio is one Zinc to 2 chlorine atoms.

https://en.wikipedia.org/wiki/Zinc

Helpful Link:

Empirical Formula Help

Formula of a Hydrate Lab

We ran the Formula of a Hydrate Lab on Monday this week, and it was very interesting and connected to our lesson perfectly. We started with Copper (II) Sulfate pentahydride (we didn't figure out that it was pentahydride until completing the lab), and we heated it using a bunsen burner. We heated the chemical in a test tube for about 5-7 minutes, then let the chemical cool before we took it's mass. We took the mass in order to figure out the mass of the water that was driven off, so we could try to find the number of water molecules in the substance. After weighing, we reheated the substance to drive off any additional water, and re-massed to chemical. Then, we calculated the number of water molecules in the substance, and determined that the answer was 5.

http://www.fphoto.com/?stockindexonline.com=1

Helpful Links:

How to find the Formula of a Hydrate

Hydrates

Today in class, we learned about hydrates, which are chemical compounds that have water in them. If the hydrate loses its water molecules, then it becomes an anhydride. The nomenclature for hydrates is simple, for all you have to do is add a prefix for the number of water molecules to the root "-hydride" to the end of the anhydrous chemical. We also learned about using hydrates to solve equations. The equations took a lot of work, but the work was fairly simple and easy to complete. The process is very tedious, though, so a small mistake could lead to a disaster at the end.

http://chemiru.com/products/ammonium-sulfate/

Helpful Links:
Hydrates
Hydrate Equations

Chemical Composition Pre Test

The Chemical Composition pre test was extremely hard. I'm not sure that I have ever seen anything on the entire test. The main things I noticed were there were a lot of numbers referring to the masses and percentages of atoms in particular compounds, but I still really had no idea what to do. As I got further and further into the test, I started just guessing, due to the fact that it was extremely hard, as well as it does not factor into my grade. Also, I am excited to learn this new material so that when the post test comes, I'll be able to actually understand what the questions are asking me to do.

http://sublimestudies.com/welcome/part4-implementation/screen-shot-2012-08-12-at-6-20-46-pm/

Helpful Links:

Definition of Chemical Composition

Empirical Formula Intro

Last Meal Conversion Project Reflection

The Last Meal Conversion Project was a very fun project. It allowed me to practice my conversion skills while converting the ingredients to my favorite foods. The conversions were normally fairly easy to do, but it got tricky when you were converting the smaller sized items such as the spices. Also, it was difficult to determine whether some ingredients were solids or liquids. For example, I made pumpkin bread. It was hard to tell whether the pumpkin mixture was a solid or liquid, so I just made my best guess at it. Overall, the project was fun, and we also get to eat everyone's favorite recipes in class tomorrow, so I am excited for that.

http://www.onceuponachef.com/2009/09/spiced-pumpkin-bread.html

Helpful Link:

Conversion Resource

Making a Mole

The mole project was an oddly easy project, for it did not take much effort to complete. We made moles to display in class for Mole day, the celebration of the number 6.022 x 10^23. This number is significant to chemistry because it is a unit that we use very commonly in the class.
There were many different approaches to the types of moles. My mole had the them of being Santa Claws Mole, but there were other themes that were much more creative. There was a Whack-a-Mole display, a metal mole, a Mole-zou mole, and many more that were very interesting. In addition, we had a party in class in which we brought in food, so the celebration of Mole day was a success.


Helpful Links:
How to Sew
Information about the Mole (unit)

Measurement Pretest

The Pretest for the measurement unit was pretty challenging. I did not know most of the information that was on it, for I have never seen most of it. I did not understand what a significant digit was, and I didn't know how to convert some of the measurements from miles to kilometers or vice versa. I believe that once I understand the concepts of the unit, it will not be very hard, but until then, I need to study and practice to ensure I understand all of the concepts.

Helpful Links:
Conversion of Units
Measurement Video

Aspirin Lab

The past two days, we did the Aspirin Lab in class. We made Aspirin out of Salicylic Acid and acetic anhydride, using sulfuric acid as a catalyst. The process of making the Aspirin was really cool, and I learned a lot about the basic processes of Chemistry in the process. First, we combined all of the ingredients, and heated the mixture for 15 minutes in a hot water bath. Then, we let it cool, poured it in a beaker, and added ice cold water in order to form the crystals. In day two, we took the mixture, and ran it through a Buchner Funnel in order to extract only the crystals out. Once we had all of the crystals into the Buchner funnel, we pulled out the filter paper with the Aspirin on it, then placed it on the lab table to dry over fall break. I am very excited to see the results after break.

http://mumbai.all.biz/aspirin-powder-g551089

Helpful Resource showing the process:

Aspirin Synthesis

Final Thoughts on the Atomic Structure and Radioactivity Unit

Today, we took our Atomic Structure and Radioactivity test, marking the end of the unit. On the test, there were a wide variety of different questions, but I was expecting more questions on the different contributions by Dalton, Thomson and Rutherford on the Atomic model. The hardest part of the test for me were the half life questions that required me to do a lot of math. I had forgotten some of the formulas, but overall I think I did pretty well on this test.

http://staff.concord.org/~ddamelin/chemsite/c_AtomicTheory/dalton.html

Also, the end of the unit means that our Star Log project is due. This project was much easier than the Frontier Chemistry Project, and took a lot less time to complete. I primarily used only three websites to gather all of my information, so the process was a lot of repetition of visiting the same sites over and over again. I learned a lot about different stars, and I also was intrigued by the different classes of stars and how their class related to their size and color.

Websites that helped me on my project:

Visual Representation of the Universe

Visual Spectrum of the Elements

Stellar Classification Help

Forensic Archaeology Lab

Today in class, we completed the forensic archaeology lab. In order to complete the lab, we had to cut out 567 squares, and simulate the process of half lives by dumping the squares out and removing the colored pieces of paper, representing decayed atoms. Then, the process was repeated 6 times in order to narrow the numbers down from 567 to about 12. The whole purpose of the lab was to correctly identify a fictional skeleton based on radioactive decay of the bones.

http://marionlocal.k12.oh.us/hs/studentwebs/2009-2010/MM/winner/CPChanges/PhysicalChanges.html

Next, we made a graph of our data in excel in order to show our results. The graph was very beneficial to me because it really helped me visualize the pattern of half lives and the severity of the drop off when half lives are accounted for.

Helpful links to reinforce knowledge of half lives:
HyperPhysics
Half Lives and Carbon Dating Video
Half Life basics

Radioactive Decay

Today in class, we learned about the three basic forms of radioactive decay: alpha, beta and gamma. The main difference between each type of radiation is their effect of the mass number and atomic number of the element. In alpha radiation, the mass  number is decreased by 4, and the atomic number is decreased by two; in beta radiation, the mass number is unaffected and the atomic number increases by one; in gamma radiation, neither the mass nor atomic number is affected due to the light energy that is given off in the gamma radiation. The basics of radiation are fairly easy for me to grasp, since there are only two big things that you have to remember for each type of radiation.

Beanium Lab

Today in class, we conducted the Beanium lab. The purpose of the lab was to determine the average atomic mass of a new element, Beanium. First, we divided up each of the isotopes of the Beanium into 4 groups; White, black, red and pinto. Then, we measured the mass of each isotope, then divided the total mass of each isotope by the number of atoms of the isotope present. Next, The average mass and percent abundance of each isotope was calculated, which gave us what we needed to find the average atomic mass of the Beanium. The average atomic mass that we calculated was .271g.

The total mass of the pinto isotope was 5.87g

Our sample was sample D, contain 42 Beanium atoms