Blog Post #10

     This past week in Chemistry we covered a lot of subjects surrounding equilibrium. We talked about equilibrium conceptually and we also did some more mathematical problems solved with equilibrium. We also saw many demonstrations of equilibrium in action and talked about how thermodynamics tie in to equilibrium. All these ideas ultimately come together  under the idea of equilibrium and predicting how different factors can react the rate at which a reaction occurs. Some important ideas to note with equilibrium are that in reality there is no left in right to the reaction. We just say left and right in order to explain better the idea of the forward and reverse reactions occurring at the same time and going both ways. Although we didn't have any actual labs this week that went along with learning about equilibrium, we did do a couple demonstrations with two beakers were we allowed them to reach equilibrium and tested to see if our RICE tables were giving us correct results. We came to understand all of the material we covered this week through various worksheets (Equilibrium I problem 9) and POGIL's. You're actually making us turn the worksheets in this time and to be honest I think it's helped me a lot because I've actually been working a lot  harder than usual on the worksheets. One question I still have about this week is why do thermodynamically unfavored reactions tend to have more reactants and thermodynamically favored reactions have more products?
     My participation this past week has been very good I'd say. I came in after school a couple times and came in today and really got some valuable feed back which I really feel like will reflect on my test score. I'd rank my understanding of this week's ideas at about a 7/10. I feel like I really understand the math behind all of the equilibrium problems and RICE tables. Some things I can work on however is the conceptual scenarios behind equilibrium and I could use a little more work with equilibrium problems that also involve thermodynamics. One of my main ideas that has changed over this past week is the thought that reactions will always go both ways. I never thought of it as constant cycle like process I always just thought a reaction kept going until there were no more reactants left.

Blog Post #9

    Calorimetry excersises), and an online activity to introduce us to entropy. We came to understand these ideas by practicing multiple problems and going over them together at the front of the class.
 This past week of chemistry has been quite intense and difficult. Some of the main ideas which we covered where entropy and calculating changes in entropy. We also briefly talked about whether reactions where thermodynamically favored or unflavored using the equation for Gibbs free energy. We learned about how entropy is the ability for molecules to occupy different spaces in different arrangements. Thermodynamics basically defines whether a reaction needs help from it's surroundings in order to occur. These topics are connected because both are used to describe reactions and their characteristics. Entropy will always change when a substance changes states  and often a change in state is either thermodynamically favored or unfavored. Some important details about these two topics are that entropy increases as heat is put into a system because the atoms go  faster and therefore can form more arrangements. Some important details about thermodynamics are that a reaction is thermodynamically favored when it doesn't require assistance from it's surroundings in order to occur. Also you can determine whether a reaction will be favored or unfavored by using Gibbs free energy. To practice all of these topics, we did multiple lecture quizzes, worksheets (
     Some questions I still have are mostly about how to calculate various things. I feel like we've learned about a hundred equations and I really need to practice  knowing when to use them. I feel like my participation this week has been decent. I've done all of the the work assigned but I feel like I just haven't quite absorbed the information as well as I could have. I also wanted to get more lecture quizzes done a day early but I just got lazy. I'd rate my understanding of this week's material at about a six. I feel like I have a basic understanding of what's going on but I definitely need more practice and I'm fairly scared for next week's test. I still need to work on calculating enthalpy and entropy in calorimeter situations. Some ideas that have changed for me is that when heat goes into a system, the temperature of the system actually goes down. I'd never actually thought of it like that before this past unit.

Blog Post #8

 

     This past week in chemistry has certainly been a busy one. Some main ideas that we focused on were inter molecular forces and how they effected different characteristics in ionic compounds. The most important inter molecular forces are London Dispersion Forces (LDF), dipole-dipole, and hydrogen bonding. Although there are a couple other important ones, these are the most important. These inter  molecular forces effect multiple characteristics of ions, one of these is boiling point. The general rule for boiling point is the bigger the ion, the higher the boiling point. This is due to the fact that there are more electrons in bigger ions. When there are more electrons the ion becomes more polarizable which leads to stronger LDF's which in turn leads to a higher boiling point. Some important details about inter molecular forces are that they are much weaker than covalent bonds and hydrogen bonding is the strongest of all inter molecular forces. We did multiple POGIL's to understand all of these activities. The most helpful was probably the one with the Femto beaker and all of the magnetic models ( POGIL on IMF's).
    I feel like I understand everything we went over this week very well and therefore don't really have any questions. My participation this week was very good. I feel like I was a very productive group member as I helped and participated in each of the activities. I would definitely say I understood everything form this past week very well. I found all of the activities relatively easy and haven't encountered too many problems. One thing I could maybe work on is explaining higher boiling points better. I understand it but I should work on explaining it better. One thing that has changed my perception is that larger ions have higher melting points.  Before this I assumed smaller ions had higher melting points because they were more tightly bonded.

Blog Post #7

   

This past week has been very interesting in class. We didn't really  go over a lot of big ideas due to the fact that we had a test and mole day was the day after. Despite all of these events however, we did begin to cover some key ideas about metals. We began to learn about how metals are malleable and ductile and are also surrounded by a sea of electrons. We also had a blast in class on mole day. The cookies were very good and complimented the hot chocolate well. Despite this we also learned and wrote an essay on the chemistry behind paint balls. Metal's property of having a sea of electrons is  what allows them to be ductile and malleable. This is because since the electrons are basically free flowing, the atoms can slide by each other thus changing the shape of the object. Some important details about this is that metals can become alloys which can change metals properties. We did a couple of POGIL's this week regarding the melting point of molecules and ionic bonds. We also watched a lecture on medals (Metals) which prepared us for our lecture quiz. 

     I still have some questions about determining the melting points of specific molecule. I understand that the charge is more important than the size but when does the size overcome the charge? My participation this week could have been a little better. I feel like I could have finished both POGIL's but I fully completed one. (I  blame Nishant). I think I have understood the material pretty well this week but I'll need to review melting point more. I found it pretty interesting how alloys of metals are so drastically different form the metals themselves. One example of this is brass which is an alloy of tin and copper.

Blog Post #6

      WebMO lab report. This lab was very important because it helps to prepare for our test. Some very important details about this lab were the shape and polarity of molecules. Shape was very important and we learned that it is determined by the number of paired and unpaired electron clouds. Polarity is also important because although the atoms in the molecules are polar, they can sometimes cancel each other out making the molecule not polar. The shape of the molecule ties in to this because often times the shape can determine if the atoms in the molecule can cancel each other out.
In this past week we learned lots o' stuff. Some of the things we learned were VSEPR, polarity, hybridization, and sigma and pi bonds. We learned some this stuff last week too but this week we put it all together with our VSEPR WebMO lab. WebMO is a program created by Hope college which allows us to model molecules. It is very helpful as it provides a good visual to molecules and provides many important details about the molecule. Using WebMO, we modeled 13 molecules and found the electron domain geometries, molecular domain geometries, dihedral angles, dipole moments, and many other things You can see my full report on this lab here:
     We came to understand all of these ideas this week through our POGIL with balloons and gum drops and the lab we did using WebMO. The lab report was kind of the icing on the cake which tied the two together. I feel like I understood everything which went into the lab report pretty well but I still have some questions regarding ionic and covalent bonds and how they tie into what we've learned. I think  participted very well in this past weeks assignments, I did all of my WebMO molecules without any issues and also was able to do my lab report and study for the upcoming test. I think I still need to work on getting lewis structures down faster because I feel like at times it takes me too long to draw them out. One thing that  really gets me thinking is the molecule BrF5 (Bromide pentafluoride). I found this molecule interesting because its unpaired electron cloud does not effect the original angles that would be made in an octahedral model made with all paired electron clouds.

Blog Post #5

     This past week has been very busy as we've learned about several new topics. Some of the main ideas we've learned about are the shapes that molecules make and polarity. The shapes made by molecules are dictated by bonded and unpaired electron clouds. This is known as the VSEPR theory. We also learned about how molecules have poles and some, based on their shape, have polarity. These ideas are connected because often polarity is dictated by shape. If a molecule's shape is symmetrical, the individual poles of electrons can cancel out meaning that the molecule as a whole has no polarity. Some important details about the VSEPR theory are that electron domain geometry shapes are often much different than molecular domain geometry shapes. This is because electron domain shapes include unpaired electrons while molecular domains do not. A important detail about polarity is that based on the molecular domain shape, polarity can cancel itself out if they're pulling in opposite directions. We did multiple POGIL's this week regarding  the VSEPR theory. The most interesting was our POGIL were we made electron domain shapes with balloons and molecular domain shapes with gumdrops and toothpicks. We also practice more Lewis structures with POGIL 14 and  POGIL 15. Through these POGIL's we learned about charges and resonance structures. We also learned about polarity through a lecture and a lecture quiz.
     We learned a lot this week and I'm definitely still a little cloudy on some subjects. Most of the questions I have are just some clarification questions regarding polarity and molecular domain shapes. I think my participation was good this week as I did all of the work and pitched in to help my group on the POGIL's. My understanding of this week's material was not as good as I'd like. I will try to fix this by reviewing the lectures again or trying to go after school some more. I still need to work on understanding polarity better and recognizing electron domain shape. Some new things I have to think about are electron clouds. I find it interesting how they can be different sizes and how they all affect each other.

Blog Post #4

     In this past week we mostly focused on our lab (That's rather brass of you, Cu) and we also began learning about Lewis diagrams. In the lab, we looked to find the mass percent of copper in a brass screw after dissolving it in nitric acid. We also learned about Lewis diagrams which are a simple way to show valence electrons and bonds in molecules. These two ideas tie well with each other because brass is actually a molecule made up of copper and zinc. In the lab, the nitric acid actually breaks down the bonds between the copper and zinc. This connects to Lewis diagrams because they represent the valence electrons and bonds in molecules. Lewis diagrams can help detail many things in a very simple way. Some details that Lewis diagrams can show are, charge, bond length, and bond order. All of these things are very helpful in identifying a molecule. We learned about the Lewis Diagrams this past week through various POGIL's and lectures. We also began to look at how bonded electron clouds look in terms of shape. We did this in a POGIL that involved tying balloons together. (See picture). The balloons are actually a fairly accurate way to portray electron clouds and really helped me visualize the shapes. The method that really allowed me to best understand the material we covered this week were the lectures. The lectures really helped me because you can watch concepts you don't understand over and over and then test your knowledge on the lecture quiz.
     A question I still have about this material is, how are triple bonds actually possible? I understand how quadruple bonds aren't possible but it doesn't really make sense to me how triple bonds actually work. I think my participation in this weeks material was good. I did all the homework and all the POGIL's so I feel like my participation was good. I'd say my one slip up however, was when our group forgot to add water to the copper solution before measuring its absorbance. I'd rate my understanding of this weeks material at about a 6 or 7. I feel like I understand what's going on but I definitely need to practice complex Lewis diagrams more and go over the electron cloud shapes. One new thing I have to think about after what we learned this week is, what happened to the zinc when we dissolved the brass screw with nitric acid and does it affect copper's absorbancy?