Monday, January 20, 2014

Blog Reflection 1/21/14



Gas Laws were taught Last week:

Boyle’s Law P1V1 = P2V2
Charles’s Law V1 / T1 = V2 / T2
Gay-Lussac's Law P1 / T1 = P2 / T2
Avogadro's Law V1 / n1 = V2 / n2
The Combined Gas Law P1V1 / T1 = P2V2 / T2
The Ideal Gas law PV = nRT
Dalton's Law of Partial Pressures Ptotal = Pa + Pb + Pc + …
van der Waals equation
Density of a Gas D=m/V
Graham’s Law r1/r2= sqrt (M2/M1)
Partial Pressure Pa= (P total)( mole fraction)
The average kinetic Energy of a Single Gas molecule KE=(½)mv^2
Molecular weight M=mRT/PV
Speed of molecules V rms=sqrt(3RT/M)


These laws all contribute to a greater understanding of the behavior of Gases. When used together, these laws allows scientists to find the speed of molecules, density, volume, pressure, temperature, number of moles, and many more things from just a few known characteristics. This is what makes these laws so great. Each law connects with each other like how Boyle’s Law, Charles’s Law and Gay lussac’s law makes the The combined Gas Law. Also, I’m a very mechanical thinking person. I really like like how these laws are “plug and chug.” In other words, the relationships are very straightforward and do not need super deep logical thinking because you can just use the formulas.  

I am  confident in my understanding of Gas laws. It would be about a 9.5/10. Like I said before, I really like straightforward, mechanical calculations. If I am given all the needed variables I can calculate the unknown. However, I did have some problems when I was given a longer problem which required multiple steps. I get really confused on those types. Luckily, there was a lot of whiteboarding and there was even a dry ice day. These activities helped me see what all the numerical variables meant in real life so I could make a faster and better connection. What also helped was that I participated with my table group during discussions and that I activity asked questions. I would rate my participation a 9.5/10 as well.
Unfortunately, I am still confused on multiple step problems. On the taskchain and chemistry worksheets, I do not know what to do because there is no clear path (By clear path I mean it is not as straightforward like finding V2 if T1, T2, and V1 is given). I think to fix this, I should just do more problems to get more experience.

After learning about Gas Laws, I am much more aware of my environment. I know why balloons slowly shrink, why dry ice makes things become tiny, and why heating something causes it to grow. I now wonder if any Gas laws like PV=nRT works on solids or liquids when the constant R is changed.