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.