September 19 Homework

Entry for September 19, 2007
Hi Chemmies! (aka late night chem class buddies)

1. I chose Iron as my element of the week. Abundant info. This will be at the end of my posting as it is the largest chunk.

2. Ozone Family & Friend discussion:

*One friend said she thought of the word "layer" when I said ozone.
*Another friend spoke about the wholes in the ozone and global warming.
*No one really know that ozone was a molecule: used in bleach, as a deoderizing agent, and used for sterilizing air and drinking water.
*The stratosphere and troposphere levels were never spoken of by my friends or family. I think the vague and general understanding of ozone being a negative in the troposphere was all anyone really thought of when asked to speak about it.
*I found it really interesting that as I was researching Iron it was mentioned that a certain form of iron in the ocean may help with reducing the greenhouse effect.

3. Review of link:
I chose the 3rd link from Purdue because, again, it was the most colorful and interesting. The other 2 sites were really boring in presentation, so I kept looking. On the 3rd link,
things were actually moving! This definitely helped me to understand the concepts of atoms, molecules, compounds and mixtures. I need all of the visuals, really all of the learning techniques available, to help my mind understand the concepts. Good link!

(Now back to #1 and my Iron info):

I pasted the most important info from wikipedia. Very interesting bit at the end regarding iron’s potential help in the ocean with the greenhouse effect!

Iron (IPA: /ˈaiə(ɹ)n/) is a chemical element with the symbol Fe (Latin: ferrum) and atomic number 26. Iron is a group 8 and period 4 metal. Iron is a lustrous, silvery soft metal. Iron and nickel are notable for being the final elements produced by stellar nucleosynthesis, and thus are the heaviest elements which do not require a supernova or similarly cataclysmic event for formation. Iron and nickel are therefore the most abundant metals in metallic meteorites and in the dense-metal cores of planets such as Earth.
Iron is one of the few ferromagnetic elements.

Iron is believed to be the tenth most abundant element in the universe, and the fourth most abundant in the Earth's crust. The concentration of iron in the various layers in the structure of the Earth ranges from high (probably greater than 80%, perhaps even a nearly pure iron crystal) at the inner core, to only 5% in the outer crust. Iron is second in abundance to aluminium among the metals and fourth in abundance in the crust. Iron is the most abundant element by mass of our entire planet, making up 35% of the mass of the Earth as a whole.

Iron is a metal extracted from iron ore, and is almost never found in the free elemental state. In order to obtain elemental iron, the impurities must be removed by chemical reduction. Iron is the main component of steel, and it is used in the production of alloys or solid solutions of various metals, as well as some non-metals, particularly carbon.

Nuclei of iron have some of the highest binding energies per nucleon, surpassed only by the nickel isotope 62Ni. The universally most abundant of the highly stable nuclides is, however, 56Fe. This is formed by nuclear fusion in stars. Although a further tiny energy gain could be extracted by synthesizing 62Ni, conditions in stars are unsuitable for this process to be favoured, and iron abundance on Earth greatly favors iron over nickel, and also presumably in supernova element production. [citation needed] When a very large star contracts at the end of its life, internal pressure and temperature rise, allowing the star to produce progressively heavier elements, despite these being less stable than the elements around mass number 60, known as the "iron group". This leads to a supernova.

Iron (as Fe2+, ferrous ion) is a necessary trace element used by almost all living organisms, the only exceptions are a few prokaryotic organisms which live in iron-poor conditions (such as the lactobacilli in iron-poor milk.)

Applications
Iron is the most used of all the metals, comprising 95% of all the metal tonnage produced worldwide. Its combination of low cost and high strength make it indispensable, especially in applications like automobiles, the hulls of large ships, and structural components for buildings.

Steel is the best known alloy of iron, and some of the forms that iron can take include: Pig iron (an intermediate step on the way from iron ore to cast iron and steel,) Cast iron, Carbon steel, Wrought iron, Alloy steel and Iron(III) oxides which are used in the production of magnetic storage media in computers. They are often mixed with other compounds, and retain their magnetic properties in solution.

Iron is believed to be the critical missing nutrient in the ocean that limits the growth of plankton. Experimental iron fertilization of areas of the ocean using iron(II) sulfate has proven successful in increasing plankton growth[1][2][3]. Larger scaled efforts are being attempted with the hope that iron seeding and ocean plankton growth can remove carbon dioxide from the atmosphere, thereby counteracting the greenhouse effect that is generally agreed by climatologists to cause global warming[4].