Saturday, May 14, 2011

Final Exam Review Question

23)    Percent Yield:
a.     The decomposition of potassium chlorate yields oxygen gas. If the yield is 95%, how many grams of KClO3 are needed to produce 10.0 L of O2?








b. If 5.0 g of H2 are reacted with excess CO, how many grams of CH3OH are produced, based on a yield of 86%?









Sunday, March 27, 2011

The Manhattan Project and the Atomic Bomb


In the 1930’s, chemists realized there was a tremendous amount of energy locked in the atomic nucleus, the only problem was accessing this energy.1 Subsequent discoveries, such as a breakthrough in nuclear fission technology by German chemists Hahn and M├ętier, opened the door for expansion into nuclear chemistry.1 However, the current state of affairs and constant conflict in the world quickly led to speculation about weaponizeing the technology. As the scientific community became both concerned and interested in the varied uses of nuclear technology, significant investments of time and money were made in the field, culminating with the creation of the atomic bomb as a result of the Manhattan project. The Manhattan Project was a significant scientific initiative to develop the first nuclear weapon. The project called for cooperation between the United States, UK, and Canada and represented a breakthrough in nuclear chemistry, one whose effects extend to present day.
The Manhattan Project was the first scientific endeavor that represented exploration into nuclear technology from a militaristic standpoint, and its origins lay in the conflict that had taken hold of almost every world power, World War II.  The project was first started out of fear that the Germans were working to develop nuclear weapons.2 Warnings of German advances in nuclear technology were first made in the Einstein-Szilard letter, written by leading German scientists Albert Einstein and Leo Szilard.1 They informed President Roosevelt that the Germans were nearing development of a powerful bomb of new nature and that they feared the German potential to use it. After witnessing the German invasion of Poland, Roosevelt decided to take action. On October 11, 1939, President Roosevelt created the Advisory Committee on Uranium that, after English advances demonstrated the feasibility of nuclear weapons and possible approaches, went to work and made significant scientific advances. Although government support was weak at first, the committee made unprecedented breakthroughs during 1940 and 1941, including potential pathways for enriching Uranium-235.1 However, as the war went on, foreign pressure and growing fear of German technological advancement forced Roosevelt to take a more direct approach. In December 1941, President Roosevelt authorized the formation of the Manhattan Engineer District of the Army Corps of Engineers (termed the “Manhattan Project”) to oversee the development of the atomic bomb.1 The Project officially began on September 23, 1942 and was centered at sites including Oakridge, Tennessee; Hanford, Washington; and Los Alamos New Mexico.3 High profile scientists such as Robert Oppenheimer, Albert Einstein, Enrico Fermi, and Ernest Lawrence worked feverishly through the next two years and by Spring of 1945 preparations began in the pacific for use of the atomic bomb.4 The Manhattan Project, grown out of the Advisory committee on Uranium, was a representation of four years of labor that culminated in a test ready atomic weapon.
Robert Oppenheimer.9
Albert Einstein.7

Enrico Fermi.8














            


             On July 16, 1945, a teat device code named “Gadget” was detonated at the Alamogordo bombing range in New Mexico.1 The successful test of Gadget marked the first detonation of a nuclear weapon and served as a testament to the beginning of the nuclear age. Gadget and the two other atomic weapons created during the project were implosion-triggered devices based on nuclear fission.5 When the bomb’s outer casing of TNT was detonated, a shockwave was created to compress the core.5 The compression began the nuclear fission reaction and detonated the bomb.5 After President Truman (Roosevelt’s successor) received word of the successful test, he began to consider the atomic bomb a viable military option, one that he saw advantageous from a strategic standpoint. The surrender of Germany on May 8, 1945 shifted the focus to Japan and called up possibilities of a nuclear strike.1 Japan’s refusal to surrender prompted Truman to seriously consider using an atomic weapon on the country. After debating the possible implication and alternatives, including conventional warfare, Truman decided that the use of an atomic weapon would be in the best interest of the United States by avoiding prolonged conflict for the U.S. armed forces. On August 6, 1945, the first offensive atomic weapon was dropped on the Japanese city of Hiroshima.1 The first bomb was codenamed “Little boy” and consisted of conventional explosive shell and an inner core of Uranium-235. The estimated damage of the first atomic strike was devastating, however the Japanese still refused to surrender. The dismissal of unconditional surrender by Japan encouraged a second attack. Three days later, on August 9, 1945, an atomic bomb codenamed “Fat Man” was detonated over Nagasaki, Japan.1 “Fat Man” was a Plutonium-239 based bomb, similar to the test bomb “Gadget” but more advanced than the Uranium-235 based “Little Boy.” The second devastating strike proved to be too much for Japan and On August 14 Emperor Hirohito announced unconditional surrender. The use of the atomic bombs developed during the Manhattan Project remains one of the most controversial foreign policy decisions to this day.4

Test of Gadget.10


Associated Press video about the first atomic bomb in Hiroshima.11


            Though the Manhattan Project and its contribution to the development of atomic weapons did end World War II, the endeavor had many other significant scientific and political implications. Positive advancements of he Manhattan project can be observed throughout the late 1900’s. For example, it demonstrated the ability of talented scientists to make significant discoveries in limited periods of time, prompting further funding of scientific research such as space exploration.6 The project also presented nuclear power as a possible alternative energy, and pursuit of nuclear power continues into the modern age and is seen by some to be a viable six for the world’s energy crisis.6 Moreover, the use of the atomic bombs created during the Manhattan project are suspected to have saved the lives of thousands of members of the U.S. armed forces because the bombings alleviated the need for further armed conflict in Japan.6 However, there were multiple disadvantages to the project as well, the most devastating being the destruction of Hiroshima and Nagasaki. The Manhattan project is also credited with ushering in the atomic age and prompting development of large-scale weapons by multiple countries. This nuclear and atomic arms race spurred the cold war and nuclear proliferation continues to be a major concern in many parts of the world.6 The positive and negative effects of the Manhattan project are a testament to the major impacts of the project itself, and the ability of a scientific initiative to alter the course of world history
The Manhattan Project and the successive development of atomic weapons served to drastically alter multiple scientific fields while changing the scope of worldwide foreign relations. The long lasting impacts of the development can be seen in modern day and the controversy surrounding the project and use of atomic weapons will continue for years to come. Both the positive and negative impacts of the Manhattan project truly changed the trajectory of society and served to usher in the atomic age.










Works Cited:

1. Kinard, Frank W. “Manhattan Project.” Chemistry Explained-the Chemistry Encyclopedia. N.p., 2000. Web. 26 Mar. 2011. <http://www.chemistryexplained.com/‌Ma-Na/‌Manhattan-Project.html>.

2. “The Atomic Bomb and the Surrender of Japan.” How Stuff Works. Discovery, 27 Feb. 2008. Web. 26 Mar. 2011. <http://history.howstuffworks.com/‌world-war-ii/‌the-atomic-bomb-and-the-surrender-of-japan.htm>.

3. “The Manhattan Project (And Before).” Nuclear Weapon Archive. N.p., 6 Aug. 2001. Web. 26 Mar. 2011. <http://nuclearweaponarchive.org/‌Usa/‌Tests/‌index.html>.

4. “Manhattan Project.” Nuclear Files.org. Nuclear age Peace Foundation, n.d. Web. 26 Mar. 2011. <http://www.nuclearfiles.org/‌menu/‌key-issues/‌nuclear-weapons/‌history/‌pre-cold-war/‌manhattan-project/‌index.htm>.

5. Freudenrich, Craig, PhD, and John Fuller. “How Nuclear Bombs Work.” How Stuff Works. Discovery, n.d. Web. 26 Mar. 2011. <http://www.howstuffworks.com/‌nuclear-bomb5.htm>.

6. Norris, Robert S. “Lessons of the Manhattan Project.” National Resources Defense Council. National Academies’ Committee on Science, Engineering and Public Policy, 5 Sept. 2008. Web. 26 Mar. 2011. <http://docs.nrdc.org/‌nuclear/‌files/‌nuc_08100901A.pdf>.



Video/Picture Sources:

7. Karsh, Yousef. Albert Einstein. N.d. malhanus.de. N.p., n.d. Web. 27 Mar. 2011. <http://www.mlahanas.de/‌Physics/‌Bios/‌AlbertEinstein.html>.

8. Enrico Fermi. N.d. Nobel Prize.org. Nobel Prize Foundation, n.d. Web. 27 Mar. 2011. <http://nobelprize.org/‌nobel_prizes/‌physics/‌laureates/‌1938/‌fermi.html>.

9. J Robert Oppenheimer. 20th Century. San Francisco Chronicle. Web. 27 Mar. 2011. <http://www.sfgate.com/‌cgi-bin/‌blogs/‌goldberg/‌detail?entry_id=38387>.

10. Trinity Atomic Bomb Test. YouTube. N.p., 26 Aug. 2006. Web. 26 Mar. 2011. <http://www.youtube.com/‌watch?v=FFZvCJYDme0&feature=player_embedded>.

11. U.S. Drops Atomic Bomb On Hiroshima, Japan - August 06, 1945. Associate Press. YouTube. Web. 27 Mar. 2011. <http://www.youtube.com/‌watch?v=N-OWTkXJUms>.





Saturday, December 11, 2010

Did I Really Just Swallow that ?!? (Part 2)


As I scanned ingredients lists on various household items I ran into some chemical compunds that prior to last week would have been mystifying. Below I listed 10 that I saw, the item they were in is listed beside the compound name in italics:

11) Aluminum Hydroxide(Gaviscon antacid)-  Al(OH)3


12) Magnesium Carbonate (Gaviscon antacid)- MgCO3


13) copper Oxide (365 everyday value [Whole Foods Brand] Adult Multivitamin)-

Copper (I) [cuprous] Oxide- Cu2O
Copper (II) [Cupric] Oxide- CuO


14) Chromous [Chromium (II)] Chloride (365 everyday value [Whole Foods Brand] Adult Multivitamin)-  CrCl2


15) Calcium Phosphate (Caltrate Calcium Supplement)- Ca3 (PO4)2


16) Phosphoric Acid (Coca Cola)- H3PO4


17) Magnesium Hydroxide (Freelax)-  Mg (OH)2


18) Sodium Chloride (Benadryl Allergy mediation [or can be found as table salt])- NaCl


19) Magnesium Sulfate (Walgreens Brand Epsom Salt)- MgSO4


20) Hydrogen Peroxide (Leslie’s Pool Supplies Baquacil Pool Shock and Oxidizer)- H2O2

To see the first 10 compounds that my partner and I found, see his blog

Wednesday, November 10, 2010

midterm review #12

Q: Explain all the exceptions to electron configurations that we have learned including the odd filling order with d and f orbitals and the exceptions among the transition metals. Why do they occur?

A: Chromium and its respective group is an exception that exists in the d block. With these elements, an electron moves from the s sublevel to the d sublevel in order to create a half filled d sublevel. This occurs because a half filled d sublevel adds significant stability due to the fact that each of the orbitals will only have one electron (b/c hund’s rule states that they will all gain one electron before they double up). The presence of only one electron in each orbital minimizes repulsions and increases stability.

Copper and its corresponding group is also an exception. The same thing that happens with chromium occurs within this group in the sense that one electron leaves the s sublevel and is added to the d sublevel. The key differences between the two exceptions is that in the copper group elements add to the d sublevel to gain a completely full sublevel as opposed to a half filled sublevel. The reason the electron moves is similar to the reason that electrons transfer in the Chromium group-to add stability. 

A third exception that occurs is between the s and d orbitals of higher energy levels. For example, the 4s orbital fills before the 3d orbital. This occurs because the vast difference in energy between an s orbital and a d orbital is greater than the difference between energy levels. Therefore, a 3d orbital has more energy than a 4s orbital. This occurs throughout the energy levels as you move past the second level. A good way to see how they fill is to write out the orbitals by energy level and then imagine that they fill diagonally.

Sunday, October 3, 2010

Chapter 4 Blog Assignment: the Discovery of Protons

To examine the Discovery of one of the three subatomic particles I decided to first take a look at what exactly a Proton is and why it is important in the Glog below.

What is a proton?

Now that the basic characteristics of the Proton have been established I went on to outline the progression of developments that led to the discovery of the Proton.

Discovery of the Proton Glog

My third and final Glog looks at one experiment in particular and examines the way it was set up and the drastic effect it had on the discovery of the Proton.

Rutherford's Experiments


**Please make sure to scroll all the way down on the text bubbles, a gray slider bar will appear that will allow you to scroll if you mouse over the right side of the text bubbles. Most of them have more written than just what is first shown and you need to scroll to see it all. Thanks

Works Cited:


-Blaimere, Professor John. “The Discovery of Protons.” Bio.edu. N.p., 4 Mar. 2007. Web. 3 Oct. 2010. <http://www.brooklyn.cuny.edu/‌bc/‌ahp/‌LAD/‌C3/‌C3_Protons.html>.

-Butt, Salaman. “Discovery of Protons.” Helium Sciences. N.p., n.d. Web. 4 Oct. 2010. <http://www.helium.com/‌items/‌1928945-discovery-of-protons>.

-“Nucleus of an Atom” Youtube.com. N.p., n.d. Web. 5 Oct. 2010. <http://www.youtube.com/watch?v=Q8RuO2ekNGw&feature=related>

-Jones, Andrew Zimmerman. “Proton.” About.com :Physics. N.p., n.d. Web. 4 Oct. 2010. <http://physics.about.com/‌od/‌glossary/‌g/‌proton.htm>.

-McPhee, Isaac M. “Rutherford and the Atomic Nucleus.” Suite 101. N.p., n.d. Web. 4 Oct. 2010. <http://www.suite101.com/‌content/‌rutherford-and-the-atomic-nucleus-a45825>.

-“1919 Discovery of Protons.” Oracle-ThinkQuest. Oracle, n.d. Web. 5 Oct. 2010. <http://www.helium.com/‌items/‌1928945-discovery-of-protons>.

-Rank, Josh. “The Proton and It’s Discovery.” Science: J Rank. N.p., 8 July 2009. Web. 5 Oct. 2010. <http://science.jrank.org/‌pages/‌5553/‌Proton.html>.

-Sawyer, Dr. Lee. “Who discovered the proton? And how was it discoverd?” Physlink.com. N.p., n.d. Web. 3 Oct. 2010. <http://www.physlink.com/‌education/‌askexperts/‌ae46.cfm>.

Saturday, September 4, 2010

Blog Posting-Chapter 2 (Chemical and Physical Properties)

For my blog posting I decided to research the chemical and physical properties of an original style Alka Seltzer Tablet. Alka Seltzer is a medicinal antacid in tablet form composed of aspirin, sodium bicarbonate, and citric acid that is manufactured by Bayer Health Care.


one alka seltzer tablet




Physical Properties:


1. White in color


2. Non lustrous
-There is no shine or sparkle evident when visually examining the tablet


3. Brittle
-The tablet does not give or bend before fracturing when subjected to stress
-easy to split or break with relatively little force


4. Mass(of one tablet)=3.808 grams
-I calculated the mass of a tablet of Alka seltzer by adding together the masses of all the active and inactive ingredients listed on the manufacturers website. The ingredients were 325mg Aspirin, 1916 mg sodium bicarbonate, 1000mg citric acid, and 567 mg sodium. The sum of all the ingredients= 1916 mg+325 mg+1000 mg+567 mg=3,808 mg= 3.808 grams


5. The tablet is a solid at room temperature


Chemical Properties:


1. effervescent 
-dissolves quickly in water, normally this would be called solubility and would be a physical property by in the case of alka seltzer it is a chemical property due to the fact that after the chemical reaction with water a different substance is produced.
-the reactants in this chemical reaction are water and the chemicals making up alka seltzer (aspirin, citric acid, and sodium bicarbonate). after the reaction takes place and the alka seltzer is dissolved in water it becomes Sodium Acetylsalicylate, Sodium Citrate, Carbon Dioxide, and Sodium Hydrogen Carbonate (the products). Because the products and reactants are different substances the reaction taking place is a chemical reaction and the ability of the alka seltzer to undergo that reaction is a chemical property of the alka seltzer.







2. Neutralizes acidity
-If alka seltzer is added to an acidic substance such as vinegar there will be a violent reaction that will slowly die down and the vinegar's acidic level will be neutralized
-the reaction between alka seltzer and vinegar is similar to the reation that occurs in your stomach when alka seltzer is ingested and the neutralization of acid is how alka seltzer relives acidic indigestion.
-to prove that acidity is nuetralized I first dropped alka seltzer into vinegar and let the reaction take place. Then I added Baking soda to the vinegar. The fact that the Baking soda failed to react proves that the acetic acid present in the vinegar has been neutralized. if the acetic acid was still present there would be a violent reaction similar to the one seen in the control (which was just baking soda and vinegar without any alka seltzer).



3. non flammable (tested)
-when exposed to an open flame, the alka seltzer tablet show no tendency to burn or ignite, proving that the alka sektzer does not have flammable tendencies



4. Tablet bubbles and Fizzes when heated
-when exposed to an open flame the tablet takes on a brownish color and then begins to bubble and fizz, similar to how it bubbles when it is put in water. Even exposure to extreme heat, however, has minimal effect on the effervescent qualities of the tablet. The tablet still has almost the same reaction with water.







5.Extremely sour and bitter taste when not dissolved in water (tested)


Works Cited:

Official Alka Seltzer Website
-http://alkaseltzer.com/as/

Alka Seltzer Original style product page
-http://alkaseltzer.com/as/as_original.html