Week 6

                    This week we began a new unit. We covered subjects such as electric charge, and the movement of particles due to that charge. We also did a lab to determine whether certain items were conductive or not conductive. Below is a picture of a whiteboard activity we did to predict how particles move in certain situations:

                    Prior to this white boarding discussion the class conducted an experiment to examine how charge effects certain pieces of matter. We used two-four pieces of tape and placed them on top of each other. After marking which tape was which, we tore the two pieces of tape from each other and examined how they reacted to a slip of paper, a metal strip (aluminum foil), and to each other. Our observations turned out to be incorrect. This led us to ask various questions to the teacher and the class to have a better understanding of the experiment. Our previous (incorrect) results consisted of trials with no reactions. This means that sometimes the metal or paper would not react with any of the pieces of tape. This was an error that may have been due to the way we ripped the tape and how close we placed the tape to the other strips. If we had put them closer this may have resulted in a repulsion or attraction among the pieces. After further examination and whiteboard discussion we found the answers to how the charges effected each other (i.e. same charges repel, opposite charges attract, etc). 

                 Next we did an lab do determine conductivity. We used a special rod that lit up if the item was conductive and did nothing if it was not conductive. We traveled around to different lab stations to test each piece of matter and record our results. Below are a few picture of items that we tested:   

               By placing the green and yellow taped rod to the solid/liquid-metal we determined their conductivity. I found the liquid metal a very interesting substance. I had minimal questions for this lab, and we white boarded our results to next day after the lab. Below is a picture of the results that we had for each tested item:

                The last day in class we moved on to a new packet that I'm assuming we will continue Monday to fully comprehend the material. I also missed a day of class because I had to make up a test, I'm sure the information we covered that day will be clear by Monday (I was sort of listening to class discussion of the info so I wouldn't miss too much!) I learned a lot this week and participated in white board discussions with my table. I also helped a lot in the collection and procedure of our two labs. Overall, it was a successful week of learning in Chem 2A!! 

                

                   

Week 5

                   This week we did multiple labs and worksheets to prepare for our test on Thursday. We also started a new unit the we will continue throughout this following week. This week we went over Empirical and Molecular formulas. We had a worksheet to practice these formulas and demonstrate our skills. The questions on this worksheet had questions such as the following: Find the empirical formula of a compound containing 32.0g of bromine and 4.9g of magnesium. We solved questions like these in the beginning of the week on worksheets like this.

                   We worked on this sheet in table groups to ask questions if we didn't understand certain problems. One question that I had trouble with and asked for help from my table/teacher was number seven. This was on the back of the paper: Find the percentage composition of a compound that contains 1.94g of carbon, 0.48g hydrogen, and 2.58g of sulfur in a 5.00g sample of the compound. We reviewed this question on the whiteboards and I understood it. 

                   We then had an empirical formula lab. We massed our clean, dry beaker. Then we added zinc pieces to the beaker. Adding 50 mL of 3M HCI after, we recorded our observations in our composition notebooks. 

                   This is a picture of the procedure we followed to conduct this lab. I think that I understood this lab very well. We wen over our results in class and I had all of the subjects I was concerned about reviewed. On Wednesday we worked on the review guide for the up coming test Thursday. Each group was assigned a job of white boarding a section on the review guide. This helped many of us (including me) fully comprehend the material for the test. I had a few questions but I didn't have to ask them because they were answered in the whiteboard discussions/presentations. 

                 Below is a picture of part of our review guide. It gives you an idea of all the material we've learned for this unit. It includes previous weeks that led up to the test. As you can see, this correlates with some of the images that I've placed above. It's a summarization of everything this unit! 

                 For this week I think my participation was well during table discussions and contributing ideas for our whiteboards, but I didn't ask my questions in class this week. That's something I can work on to do better at this week. That concludes my fifth week in Chemistry 2A. 

Week 3/4

                    These past two weeks covered a lot of material. First we reviewed relative mass. We were given a worksheet and conducted a lab to practice massing objects and using our data to solve problems and create contrasting ideas. There was a lot of math involved in the material we reviewed that day. It included word problems that required various math skills and thought. Through this activity I learned (practiced) how to use the data collected and apply it to real life situations, as shown on the following worksheet:

The worksheet gave us many problems to apply our data to. These are situations that could potentially occur in real life! A question I have is: in certain situations, how do you determine which units to use in your final answer? 

                  Next we reviewed what a mole in chemistry is. First we had a journal about it to write down our initial thoughts. The mass of a mole of a substance is called the molar mass of that substance. The molar mass is used to convert grams of a substance to moles. My understanding of this concept is quite good, due to the multiple labs and worksheets that we had on it. But I still have a few questions about conversion that I will ask Ms. Hetter and my table mates one on one. Therefore, I rank my understanding a 9/10. In class, we read an article all about moles in chemistry. Here is an image of our activity!

After thoroughly reading this article the class began conducting labs (in the next few days). After burning and masses the given substances (zinc chloride) on bunsen burners, we recorded our data and applied it to the problems on our worksheets. We had to make sure to wear safety googles as we observed our zinc chloride smoking. Previously, we had massed zinc, then massed the zinc chloride. Then by subtracting our first calculation from the second, we mathematically predicted the mass of chlorine in the zinc chlorine. I still need to work on how to know which pieces of data to use in certain calculations like the ones in this lab.

                    Lastly we practiced finding the molar mass of compounds, etc. Below is an example of the work we did in class... And below is also the color coding we did, to show which elements were diatomic on the periodic table. This helped prepare us to work with the compounds and elements in the following activities.

After calculating molar mass on our worksheet, we showed our work on whiteboards and presented the information to the class. This was a plus for participation points since I presented our information (not for this board) :) The worksheet required us to divide given information by the estimation of a mole and number of molecules, etc. It took some time for our group to understand the material but we finished the worksheet by the end of class. I still struggle a bit with the math used in the pictures above. How do you eliminate certain units? And how do you determine what data to multiply and divide by the other data? 

That sums up the material that we covered in week 3 and 4 of Chemistry 2A. We generally covered mass, ways to demonstrate mass (i.e. moles, grams, etc.) , and how to apply that information to mathematical and real-world problems.