Saturday, December 11, 2010

Chemistry is Everywhere

When searching through our pantires and the aisles of the supermarket, we came across many different compounds further proving that.... CHEMISTRY IS EVERYWHERE!

Velveeta Cheese
1. calcium phosphate



Velveeta Cheese
2. sodium phosphate



Hormel Pepperoni
3. sodium nitrate



Safeway Disinfecting Wipes
4. ammonium chloride



Liquid Plumber Power Gel
5. sodium hypochlorite



Liquid Plumber Power Gel
6. sodium hydroxide



Fancy Feast Cat Food
7. potassium chloride



Fancy Feast Cat Food
8. zinc sulfate



Fancy Feast Cat Food
9. copper sulfate



Fancy Feast Cat Food
10. potassium iodide



Fancy Feast Cat Food
11. magnesium sulfate



Fancy Feast Cat Food
12. salt
 



Fancy Feast Cat Food
13. calcium carbonate



Fancy Feast Cat Food
14. iron (II) oxide



Fancy Feast Cat Food
15. cobalt (II) carbonate



Medical Scrub
16. ammonium sulfate



Herb Seasonsed Restaurant Style Croutons
17. calcium sulfate



Herb Seasonsed Restaurant Style Croutons
18. sodium acetate



Centrum Kids
19. magnesium oxide



Centrum Kids
20. manganese (II) sulfate
 

Tuesday, November 9, 2010

Trimester 1 Exam Review:

Question #19:
Give three distinct examples of quantum number combinations that cannot occur, and explain why they are impossible. Each example should illustrate a separate violation.


Example A)
(0,0,3,-1/2) - This combination cannot exist because the n #(the energy level) cannot be 0. 


Example B)
(3,3,1,1/2) -  This combination doesn't exist because it has the n and the l numbers the same.This is not possible.


Example C)
(1,2,1,1/2) -  This combination doesn't work because of the n and l numbers. The second number (l=2) represents a d orbital, but level (n=1) does not have a d orbital, making these quantum numbers impossible. 

Saturday, October 2, 2010

The Discovery of a Neutron

               Today, we take for granted our knowledge of the atom. But, this knowledge is very important to our world and if it wasn't for many hardworking scientists, we wouldn't have it. In this post I will tell you about the discovery of the neutron, a neutrally-charged particle in the nucleus of an atom.

1) Ernest B. Rutherford

               In 1897 the electron with a negative charge was discovered by J.J. Thompson and it seemed to orbit around the nucleus. Later, in 1918, Ernest Rutherford made the discovery of a positively-charged proton within an atom that seemed to cancel out the negativity of the electron, creating a neutral atom. After all of these findings, many thought that this was the make-up of an atom, just the protons and electrons, because they did cancel out each other to make a neutral charge. All of this information still didn’t stop Ernest Rutherford from contemplating another part of the atom. In 1920, he theorized that there was a neutral particle in the atom with around the same mass of a proton. His reasoning for this was because of the atomic number and the atomic mass. The atomic number of an atom is the number of protons it contains while the atomic mass is the mass of the nucleus. He was finding that the atomic mass was usually greater than the atomic number, demonstrating that there was something left to discover.
 2) James Chadwick

               In 1932, a scientist by the name of James Chadwick decided to put a decade of theory to the test and prove that there really was another neutrally-charged particle in the atom. He performed tests on a new type of radiation that had been puzzling scientists for years. It was previously mistaken as “gamma rays” (a form of radiation consisting of high-radiation photons) but Chadwick was out to prove this was not true. This type of radiation was electrically neutral and was discovered in 1930, just before it was used in Chadwick’s famous experiment. The radiation seemed to be coming from the nuclei of light elements that had been exposed to other types of radiation. At this time, many scientists had been thinking that they had found new types of particles but most of them turned out to be clusters of already known particles. Because of this, many thought that Chadwick was wrong and was just dealing with the known “gamma rays” which have no mass. In order to prove them wrong, Chadwick tried to determine the new particle’s mass and if it was approximately equal to that of a proton.
              Although this thought may sound easy, it was not. A subatomic particle is not something someone can just place on the scale and weigh. But, Chadwick came up with a solution. The masses of the nuclei of many elements were already known at the time and techniques for measuring the speed of the fast-moving nucleus had already been developed. So, he decided to force the mysterious new particles into samples of selected elements. He thought that when a direct collision occurred between the new particle and the nucleus of one of the target atoms, the nucleus would be knocked out of the atom, and he would measure the velocity.

              After all of this information, you are probably thinking, why is this important? Well, the discovery of the neutron helped us to understand the make-up of the atom. The neutron actually plays a big role in the stabilization of the atom, equal to that of even a proton. Also, neutrons play an important role in the process of creating nuclear explosions and nuclear energy. This is because the bombardment of high-energy neutrons is how a scientist can split an atom. 


Works Cited:


"Chadwick Discovers the Neutron 1932." PBS: A Science Odyssey. WBGH Educational
       Foundation, 1997. Web. 3 Oct. 2010. <http://www.pbs.org/wgbh/aso/
       copyright.html>.



"Chadwick's Experiment to Discover the Neutrons." Major and Minor Worlds. N.p.,
       n.d. Web. 3 Oct. 2010. <http://library.thinkquest.org/C001124/gather/
       aexp.html>.



Crowell, Benjamin. "The Discovery of the Neutron." Lectures in Physics. N.p.,
       n.d. Web. 31 Mar. 2006. <http://www.vias.org/physics/bk2_05_05.html>.



"James Chadwick." The History of Computing Project. N.p., 21 Mar. 2010. Web. 3
       Oct. 2010. <http://www.thocp.net/biographies/chadwick_james.htm>.



McPhee, Isaac M. "The Discovery of the Neutron: James Chadwick's Remarkable
       Experiment." 
Suite 101. N.p., 27 Feb. 2008. Web. 2 Oct. 2010.
       <http://www.suite101.com/content/the-discovery-of-the-neutron-a46060>.



Trinh, Hoc. "James Chadwick and His Discovery of the Neutron." Helium. N.p.,
       n.d. Web. 3 Oct. 2010. <http://www.helium.com/items/
       216709-james-chadwick-and-his-discovery-of-the-neutron>.



Pictures:

1)  Ernest Rutherford. N.d. N.p., n.d. Web. 3 Oct. 2010. 
         <http://3.bp.blogspot.com/_mg678rIGDbY/R2b0wHtaV6I/AAAAAAAAAAU/A-03hJoSR1A/
           s320/ernest_rutherford2.jpg>.

2) Corbis, J. English Physicist James Chadwick. N.d. Wired. N.p., n.d. Web. 3 Oct. 
         2010. <http://www.wired.com/science/discoveries/news/2009/02/dayintech_0227#>.

3) Hamilton, Calvin J. James Chadwick's Experiment. N.d. Solar Views. N.p., n.d. 
        Web. 3 Oct. 2010. <http://library.thinkquest.org/C001124/gather/ 
        aexp.html>.

Video:

Discovery of NeutronsTutor Vista. N.p., n.d. Web. 3 Oct. 2010.
        <http://www.youtube.com/watch?v=HnmEI94URK8>.

Saturday, September 11, 2010

Cotton Candy Chemistry

Description

Cotton candy, a delicious sweet treat, commonly found at a baseball game, is a very fun object to experiment with. It has many physical properties that are apparent to the naked eye, but also some that need physical testing to prove. Also, some very interesting chemical reactions occurred.


Physical Properties:


The amount that we used for each experiment was not exact, but it was about this amount each time.

- Soft
- Malleable
- Blue in color
- Sticky
- Dissolves in water



Chemical Properties:

We did multiple tests and they proved many chemical properties of cotton candy.

1. Cotton candy is NOT flammable
We held the flame to the cotton candy and although it melted, it did not produce it's own flame, demonstrating that it is not flammable.


2. Cotton candy has an odor of sugar and tastes sweet. We obviously tested this one, because of how amazing cotton candy is! Christina and I smelled it and it had a sugary smell and Christina tasted it and it was sweet like sugar.

3. When set on fire, cotton candy crystallizes. We set the cotton candy on fire and although it did not maintain its own flame, it crystallized into a thicker solid. 






4. When heated, the cotton candy first forms a liquid, shown below:




-Then it changes color into a greenish blackish hue:






-Finally, when cooled, it forms a hardened black and green crystal. This demonstrates a chemical change because of the change in color.




5. Finally, we performed an experiment with water, yeast, and cotton candy. First, we combined water and yeast in a plastic bottle:






-Then we put the cotton candy into the bottle and placed a plastic bag on the top to capture any gas that could possibly be formed:




-Next, we waited and checked it every five minutes and within 10 minutes, it formed bubbles and a new gas, what we thought was carbon dioxide. The reason this happened was because the yeast ate away the sugars and produced a gas:






-Next, to prove that this was carbon dioxide, we did yet another test. I know that some fire extinguishers are made up of liquid carbon dioxide that comes out as a gas so to prove that this was also carbon dioxide, we lit a match and stuck it in the bottle of gas:



video

-As you can see from the video above, this gas was indeed carbon dioxide. This whole experiment showed that yeast and water combined with the sugars of cotton candy to create a whole new gas, making it a chemical change.