Week Three

Transitional Metal of the Week:  Iridium

Iridium is the rarest non-radioactive, non noble gas element in the earth's crust. It's abbreviation is Ir, it's atomic number is 77.  A member of the platinum metal group, it is white with a yellowish tint.  The name Iridium is Latin and means "of rainbows" because many of its salts are strongly colored.  Iridium is very brittle and hard and therefore very hard to work with.  It's main use is as a hardening agent in platinum alloys.  Although it is rare in the earth's crust it is common in meteorites.  Scientists believe that the dinosaurs were destroyed by a meteorite because Iridium has been found in a clay mixture in the earth's crust that dates back to the K-T Boundry 65 million years ago.  It is the most corrosion resistant metal known.

Different Molecular Structures Of Carbon

Mmmn.  I figure there are two forms in which pure carbon occurs:  diamond & graphite.  This is sort of odd because diamonds are notoriously hard and graphite is sort of soft and greasy. This is possible because although both forms are made entirely of carbon atoms their structure varies greatly.  In diamond, each carbon atom is bound to four other carbon atoms in a tetrahedron pattern.  This structure makes diamond very hard.  In graphite, the carton atoms form sheets of linked hexagons that look a lot like chicken wire.  Each carbon atom within a sheet forms strong bonds to three other carbon atoms but the stacked sheets are only held by weak bonds.  The sheets can slide past each other.  That gives carbon its soft feel.

Website Review

Ok, I have to be straight with you.  I'm not much for math or chemistry.  It's not that I don't want to be, but somehow my brain is not wired that way.  I found the link: http://www.visionlearning.com/library/module_viewer.php?mid=55 to be quite helpful to me.  This link laid the bonding issue out like a book which made it much easier for me to comprehend.  I was present in class Wednesday, but I managed to miss the idea that ionic bonds don't share electrons and covalent bonds do.  That's a pretty big piece of info. to miss.  This website took me through what I probably missed and today I feel I have a whole new understanding.  I feel so empowered....

Week Two

Element of The Week: Argon

Argon's atomic number is 18. It is a noble gas, so it's S & P orbitals are full making it very stable. It's abbreviation is Ar which in Greek means "the lazy one" because it's full orbitals dissuade it from combining with other elements. However, scientists in Helsinki were able to make compounds by blasting Argon ice with UV rays in 2000. It accounts for 1% of our atmosphere making it the most prevalent noble gas on earth. Mercury's atmosphere contains about 70% Argon. Ar has no color, taste, or odor and is non-toxic both as a gas & in a liquid state. Argon is the least expensive noble gas, so it is used widely in industry. Pipefitters use it to purge pipes because it doesn't oxidize. It is used in fluorescent lighting and to extinguish fires on equipment that would be damaged by water.

Ozone

Isn't That the Indoor Playground That Serves Really Bad Pizza?

I was surprised by that my associates were so knowledgeable and opinionated about ozone. As the subtitle indicates it isn't really something that I have devoted much time or energy to analyzing.

The most mainstream of my sources believes that ozone is being depleted by our activity down below. In the future we will all be suffering from skin cancer. Being fair skinned I should go to the Dr. and be checked to make sure I am not disfigured or consumed by it.

One of my sources is extremely well read. He believes anyone interested in the topic should read "Cool It" by Bjorn Lomborg. Lomborg's research indicates there is an increase of CO2 in the atmosphere and that worst case scenario earth's temperature would raise by 3 degrees. Warming might actually benefit us as a population because more people die from being too cold than warm. To try to do anything about the problem is quite expensive. The world has a lot of problems...malaria, malnutrition, and so on. Spending resources to bolster the ozone is wasteful. Spending the same money on about 10 other problems will benefit mankind 10 to 50 times over. Everyone concerned about this problem should read the book and get busy on projects that are helpful. Hold on it's going to get a bit inflammatory....Don't buy Al Gore's hype!

Here's my favorite opinion:

Ozone is three Oxygen atoms bound together into a molecule. It's used in water treatment to sanitize water because it's relatively unstable. The 3rd atom separates easily and "oxidizes" what it touches. Ozone occurs in the upper atmosphere. When it comes into contact with other molecules, it reacts. People can measure ozone concentrations. On the ground, on hot summer days, it's a pollutant. In the air, above Antarctica during cold winters, ozone dissipates. In debate, Ozone is also useful. One can use it to convince people to submit to the tyranny of experts.

Link Review

I enjoyed this link:

http://chem.purdue.edu/gchelp/atoms/element.html

The link is short and simple to understand. It has great pictures that move. I was able to get all the way through it and increase my knowledge.