A mole

When learning about the Mole, at first I thought it was going to be really complicated and confusing. I thought that it would be hard to grasp. In actuality it really made more sense then I thought it would.  For me it was common sense to use the mole as a conversion factor, especially when we started stoichiometry. That doesn’t mean I always know how to solve the problem, but when I get what to do I know how to do it. Today I had an aha moment when I was doing my glog. I realized how there could be a mole of molecules and a mole of atoms. It should have been obvious but it took me this long to realize a mole of molecules accounts for a mole of each atom. Now I know that Avogadro’s number (6.02×10^23) is a mole. And I know that it is used primarily for calculations to bring the molecular world into the visual world. Last but not least, having to do moles made me look more closely at the keyboard and now I know where the exponent button is (it is Shift 6).

 What do you call the number of molecules in a mole of guacamole? Avocado's Number  | Chemistry Cat

http://chemistry.about.com/cs/generalchemistry/f/blmole.htm

http://memegenerator.net/instance/42515485

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Write-Away Firday: Woodlawn Bus Tragedy

This week I had and have (I have performed but there are still performances tonight) the opportunity to experience and share an experience from the past. This was an accident that occurred on a bridge near Fort Sumner in 1972 the day after Christmas. There was two buses traveling from Texas to New Mexico. The first bus passed a tractor trailer and did fine. The second bus however was hit. ” In the flash, Roberts (the driver of the first bus) witnessed the behemoth cattle truck and the trailing bus crash with such ferocity that the collision ripped the bus frame from its body.” Nineteen people killed and sixteen of them where teenagers. I wasn’t there and I don’t quite think my words could even compare to that of the people who where there. The article describes the words of the victims of this accident in a way that clearly says more than I ever could.

 

“Survivors describe the outlines of terrifying, heart-wrenching scenes — the cries for help, the heroic, frantic efforts to comfort and tend to the injured, the limp and lifeless bodies tangled in the heap. The collision sent luggage hurtling from the back of the bus and wrenched seats loose from the floor moorings, pinning the victims.

“You knew friends were dying,” Wesson said.” 

 

This next portion of the blog is my part in Ghosts of the Past. Although I did the research in the character and added ideas to the script,  it was actually written by Megan Rupp.

 

 

 

WOODLAWN BUS TRAGEDY SCRIPT ~ LAURA COGGINS

 

October 2013

 

 

 

(Laura is laying on the ground partially covered by a jacket. She is dazed.) Do you know where the bus is? I can’t find it. I should be on the bus… I can’t believe I ruined my new dress! I just got it yesterday. It was a Christmas present. Mom only let me wear it on the trip, because I promised I wouldn’t get it ruined. Why do I always mess things up? I can’t find the bus… (suddenly very aware.) That’s right. I forgot. The bus is gone. There was a flash of sparks. They looked like Christmas Lights. Then there was a loud crunching sound and my head… it hurt. There was glass. It was broken. The seat was bent. I couldn’t get out! I couldn’t get out! (frantic, grabbing at stomach) Help! Help! It hurts… It hurts… (suddenly calm) Mom’ll be mad that I ruined my new dress. How could I do that? Now I’ll never wear it to Friday Great Hall… and I was gonna finally get Jimmy to notice me… It’s not fair. My stomach hurts. It hurts. It hurts. It hurts! (crying) Why does it hurt? WHY? Where is the bus? I should be on the bus… We’re going to the Bible Retreat. We’re gonna ski…and have fun…We were singing…
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(singing, haltingly)
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Lean on me, when you’re not strong. And I’ll be your friend. I’ll help you carry on. For it won’t be long…

 

‘Til I’m gonna need somebody… … to lean on. (Laura’s eyes close and her head falls.)

 

I know history is important and that it is stories of life-changing experiences. I think remembering the past helps to honor those that have had these sorts of tragedies. As well as the bravery of those who were there helping the ones that were injured or didn’t survive. So far I think my performances have captivated the audience and I have share these peoples lives with those who have come to see. I plan to also do a spectacular performance tonight to show that those people matter.

40 years after Woodlawn bus tragedy, survivors recall horror, then outpouring of compassion photo

http://www.statesman.com/news/news/local/40-years-after-woodlawn-bus-tragedy-survivors-reca/nTfg4/

Write-Away Friday Ballroom Dance

1. What tasks have you completed recently?

  2. What have you learned recently? 

3. What are you planning on doing next?

I am super excited because I have started a dance class (that is more like a club) at NMSU and I am learning ballroom dance. Two weeks ago I learned the Country two step. This past week I didn’t attend but I want to continue to go in the future.  I absolutely love it. I also went the next day to another dance class like this one but I missed the class portion due to other commitments and I just did the social dance after. Throughout the night I learned a little bit about a lot of dances. I did west coast swing, waltz, and a whole bunch I can’t remember the name of. What was the best though was following the leads that knew how to dance. I got to do things like dips, spins, and countless other moves. I will continue to go and instead of following pathetically I will know what I am doing as I go more and more. Oh and another thing that I learned through this experience is that when you dance and “step on the other persons toes” or mess up don’t say sorry. All most all of the people I danced with told me to act like I meant to do it. ( I was very bad at this).

  


http://inav.net/dance/ponderos.html

How To – Percent Composition

In order to do percent Composition it is imperative to know what it is.  According  to Anne Marie Helmenstine, Ph.D. “percent composition is the percentage by mass of each element in a compound. ” That means the end result will tell what percentage of the weight is a certain element such as carbon, hydrogen, or water. There are two equations that will find this number. They are exactly the same thing it just depends on the definition that is easier for you to remember. They look like this: 

The best way to understand this is by example, so we will start with a practice problem to solve. The Problem is:

What is the Percent Composition of Carbon in Ethane(C2H6)?

Step number 1.Multiply the subscribes of Carbon (AKA number of atoms) times the atomic weight from the periodic table (it is written in amu) and that is  2 x 12.011=24. 022

Step number 2. Find the Formula weight. The only difference this time is it won’t just be the part we are looking for, it is the entire equation and that looks like: C:2(12.011)+ H:6(1.0079) = 30.0694

Step number 3. Use your answer from step one or the Carbon weight (in this case Carbon) divided by Step two or the Formula weight. It looks like 24.022/30.0694= .798885

Step  number 4.  Lastly find percent by multiplying the quotient by 100. So that looks like .798885 x 100= 79.8885%

Most likely I would round that to 80% or 79.89% depending on the situation and how accurate the information needs to be.

Now its time to think about how this is useful in chemistry. Remember “percent composition is the percentage by mass of each element in a compound. ” Or in other words the answer is the number of grams of Carbon in a one hundred gram sample of Ethane. So using that ratio it is possible to determine how many grams of Carbon is in any sample of Ethane. So if you needed to know how much Carbon is in 36.17g of Ethane you would use the percent composition to determine this. it looks like :

Therefore for this particular problem to know how much Carbon is in 36.17g of Ethane the calculation would be

36.17g C (79.8885g C)/(100g)= 28.8957 g of Carbon.

From these calculation and more it is possible to calculate the Empirical Formula of a substance. So in order to demonstrate this we will again use an example using the Percent calculation to go to Empirical Formula.

If 40.0% is calcium, 12.0% is carbon, and 48.0% is oxygen, what is the empirical formula? To figure this out use the steps below and I will show the calculations below to help clarify what to do.

Steps Ways to Complete the Step
1. Mass % of Elements Assume 100 gram sample
2. Grams of Each element Use Molar Mass
3. Moles of each element Calculate mole ratio using the smallest mole
4. Empirical Formula  

Ca 40%= 40g,    40g (1 mole/ 40.08g)= .998004moles,   .998004/.998004= 1

C 12%= 12g,    12g(1 mole/12.011g)= .999084moles,   .999084/.998004= 1.00108 or 1

O 48%= 48g,    48g(1 mole/15.999g)= 3.00019moles,   3.00019/.998004= 3.00619 or 3

So the empirical formula is CaCO3.

The reason this is important is because the last number could be and in this case is the identity of the substance. The only way it wouldn’t be is if the actual formula  or molecular formula was something like glucose that is C6H12O6 which is not the smallest ratio like the empirical formula which is CH2O. But this formula tells us what the element is. And it is Calcium Carbonate.

 

 

 

http://chemistry.about.com/od/chemistryglossary/g/Percent-Composition-Definition.htm

https://mail-attachment.googleusercontent.com/attachment/?ui=2&ik=305ded3dca&view=att&th=141d310f113d2348&attid=0.1&disp=inline&safe=1&zw&saduie=AG9B_P9UpMvbGrqi8zeIX32k2HXv&sadet=1382225693830&sads=L3_aMpYF1rc2AWzH–GBIpIw8u4&sadssc=1

https://mail-attachment.googleusercontent.com/attachment/?ui=2&ik=305ded3dca&view=att&th=141d35792da6e916&attid=0.1&disp=inline&safe=1&zw&saduie=AG9B_P9UpMvbGrqi8zeIX32k2HXv&sadet=1382230687208&sads=n3TYid3QLiE5wQapRObS_RsvuJs

http://upload.wikimedia.org/wikipedia/commons/d/d3/Calcium_carbonate.png

https://sweetpea1096.files.wordpress.com/2013/10/b1596-caco3.gif

H. Chem Problems in Dropbox

Write-Away Friday

1. What tasks have you completed recently?  

This year starting on August 11 I decided I was going to read the entire Book of Mormon again and I was going to finish it by my 17 birthday. I gave myself 52 days to complete this 500+ page book. If you can do math then you know that is about 10 pages per night. Well lets just say I procrastinated slightly and found myself reading about 20 pages for the last week in order to complete my goal.. I am proud to say that I did complete it by my Birthday, but I also learned a few things about goal making.

2. What have you learned recently? 

There is a S.M.A.R.T way to make a goal. 

Specific

Measurable

Attainable

Realistic

Timely

I had a specific goal. It was measurable, Attainable, Realistic, and Timely, but I realized that I needed to put more energy into my goal to get it done. So with this goal I learned that just because you can do it, doesn’t mean you will do it. So I learned with a goal the Best advice to have once you get a good goal is to DO IT!!! And not procrastinate.

 

3. What are you planning on doing next?

Well This year in my seminary class (church class) we are studying the Book of Mormon. I have decided that I am going to read it again by the end of the school year, but I will try to study it more and make goals from it to improve my life. 

http://meridian6yw.blogspot.com/2012/07/book-of-mormon-challenge-reminder.html

Science by the Numbers

Collecting quantitative data in science is all about accuracy and precision. Accuracy is being as closes to the actual measurement as possible, while precision is the repetition of the same result. It can be represented by the following diagram.

precision vs accuracy slides_Page_6

In science it is important that there is accuracy and precision especially in chemistry on the atomic level, because the difference between atoms is so slim that without accuracy and precision there would be a lot of confusion and falsities among the atom and elements.  Like for example the element Selenium’s atomic mass recently changed from 78.96(3) to 78.971(8). The difference between the two is .0088 amu. The article, stated that ” For the other 15 elements, the new weights were determined through better measurements and the changes are much more subtle.” Emphasis on much more subtle. I don’t know about you but .0088 amu does not seem to be that big of a difference, but in this case it was a big difference.  An example of where this difference matters comes from this article in an experiment in 2005.   They used Silicon and Sulfur to determine the validity (accuracy and precision) of  E=mc^2. On such a small extreme the littlest things can make all the difference and can be the difference of proving or disproving E=mc^2. Also with data Scientists use significant digits. The last number in a calculation is always and estimataion. There is only so much that can be measured because of the limited tools we have.

For example, if you have a ruler with only centimeters on it and you measure a pencil like the one in the picture. You can see that is for sure 16 cm. But you don’t know 16 and what. I estimate it is 16.0 cm but in reality it could be 16.0000000000001 cm. but because there is no way to measure that , then I can only say 16 and guess its .0 over that.  This estimation helps to make the data as accurate as possible.  Post what you get for the crayon on your own to see if you get significant digits. In science All data uses significant digits, precision, and accuracy so that it can be as reliable as possible. Its all about reliable data so that the conclusion we make about the world around us are correct and repeatable.

http://dl.clackamas.cc.or.us/ch104-01/precision%20vs%20accuracy%20slides_Page_6.jpg

http://www.eduplace.com/math/mw/background/1/10/te_1_10_overview.html

http://www.livescience.com/39912-atomic-weight-changed-for-19-elements.html