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Catching Elephant is a theme by Andy Taylor
Although they are identical chemically, diamond and graphite differ greatly in their physical forms. Diamonds are very hard, one of the hardest substances known to man, but it is a poor electrical conductor; whereas graphite is soft and a great electrical conductor. Both have different purposes in our everyday life: Diamond is often used for industrial cutting due to it’s strength, whereas graphite can be used as pencil lead or lubricant. Minerals that have similar chemistry but different crystal structures are called polymorphs. But what gives rise to these extreme physical differences?
The differences between polymorphs are due to their crystal structures.
Graphite is formed by sheets of hexagonal carbon units (6 carbons per hexagonal unit) stacked upon each other. Within each sheet every carbon atom is bonded to three adjacent carbon atoms, Each carbon atom has four available valence electrons for bonding. Three of these electrons are used in forming bonds with adjacent atoms in the sheet. The fourth, un-bonded electron is free to wander over the surface of the sheet: This is why graphite is a great electrical conductor. The sheets are held together by van der waals forces, and because these forces are weak the sheets can easily slide with regards to each other, which results in the softness of the substance.
Diamonds are structured so that each carbon atom is strongly bonded to four adjacent carbon atoms. The four valence electrons of each carbon atom form very strong covalent bonds. These bonds have the same strength in all directions, giving diamonds their hardness.
The physical properties of every substance relates to it’s molecular structure and it’s various intermolecular bonds, whether it be purely carbon, or any mixture of atoms or molecules.
A simple Hydrogen Bonding video.
Vulcanization, ha ha.
(Nov. 28, 2011)
Physicists from the University of Stuttgart show the first experimental proof of a molecule consisting of two identical atoms that exhibits a permanent electric dipole moment. This observation contradicts the classical opinion described in many physics and chemistry textbooks.
A dipolar molecule forms as a result of a charge separation between the negative charged electron cloud and the positive core, creating a permanent electric dipole moment. Usually this charge separation originates in different attraction of the cores of different elements onto the negative charged electrons. Due to symmetry reasons homonuclear molecules, consisting only of atoms of the same element, therefore could not possess dipole moments.
However, the dipolar molecules that were discovered by the group of Prof. Tilman Pfau at the 5th Institute of Physics at the University of Stuttgart do consist of two atoms of the element rubidium.
I was watching a video, and in the comments I found that someone said, ” If you want someone to learn about something, why don’t you turn it into a video game? So many people play video games! “ And I find that I can’t really disagree with him.
It’s not necessarily true for everyone, but I think there are many people who would much rather throw themselves into an interactive world then delve into a textbook. Sure, there would be many subjects that would be very difficult to put into game format, but I think it could be done.
Instead of reading a textbook, a person could learn ” the rules of the game”, and then be put into a semi- realistic scenario where they could use their best judgement and apply that knowledge.
People do this with video games all the time. You have to learn how the video game works before you can play it, and then you are ready to go. And you are not an expert right away, but with practice, and with being challenged with progressively harder scenarios, you become better at the game.
I know I would play a video game that taught me things about different fields.
While there would be problems like ” the game scenarios are predetermined, and it doesn’t vary, it’s already programmed into the game”, it would still be interesting, maybe even useful.
felper said: Aaaaah! I love carbon structures!! Just thinking that diamond and graphite are essentially the same arranged in a different way, blows my mind!!
I know. I just had to upload this picture.
I agree ! Carbon structures have always been my favorite. I mean, like you said, just that slight difference in arrangement brings about different properties? The very fact that a slight difference in arrangement creates different properties is so amazing to me.
One’s a great electrical conductor, the other isn’t. One is softer, and the other is hard.
Magnesium
Magnesium, no. 12 on the periodic table, and Mg for short, is the fourth most abundant mineral in the body, and is necessary for good health. It is a grayish-white metallic material also found in the Earth’s crust, but not in its elemental form. This element tarnishes, (dulls), slightly in air and ignites fairly quickly. When ignited, magnesium burns with a fascinating white flame.
Magnesium is said to have been discovered in 1618, when a farmer gave his cows water to drink from his well. However, the cows would not drink the water because of a bitter taste. The farmer later noticed that the same water healed scratches and rashes. Eventually, this healing substance came to be recognized as magnesium sulphate. Magnesium was discovered by Sir Humphrey Davy in 1755 in England. It was isolated when he mixed the earlier mentioned magnesium sulphate with mercuric oxide, and was then electrolyzed. Magnesium has a melting point of 1202 F, (650 C), and a boiling point of 1994 F, (1090 C).
Astatine?
More like ASStatine.
If you ever need to review the basics of early chemistry, this is a pretty childish but very fun way to review.
I have a quick question for chemistry people/chemistry majors. If you have time.
I like this periodic table a lot. It’s really organized, and helps me with my homework. I just thought I would show you guys.
Is anyone online that I can ask a quick chemistry question?
Decades Old Mystery of Buckyballs Cracked
After exploring for 25-years, scientists have solved the question of how the iconic family of caged-carbon molecules known as buckyballs form.
The results from the Florida State University and the National Science Foundation-supported National High Magnetic Field Laboratory, or MagLab, in Tallahassee, Fla., shed fundamental light on the self-assembly of carbon networks. The findings should have important implications for carbon nanotechnology and provide insight into the origin of space fullerenes, which are found throughout the Universe.
Many people know the buckyball, also know as fullerene by scientists, molecule, C60, from the covers of their school chemistry books. Indeed, the molecule represents the iconic image of “chemistry.” But how these often highly symmetric, beautiful molecules with extremely fascinating properties form in the first place has been a mystery. Despite worldwide investigation since the 1985 discovery of C60, fullerene has kept its secrets. How? It’s born under highly energetic conditions and grows ultra fast.
“The difficulty with fullerene formation is that the process is literally over in a flash – it’s next to impossible to see how the magic trick of their growth was performed,” says Paul Dunk, lead author of the work.
In the study, published in Nature Communications at the end of May, the scientists describe their ingenious approach to testing how fullerenes grow. “We started with a paste of pre-existing fullerene molecules mixed with carbon and helium, shot it with a laser, and instead of destroying the fullerenes we were surprised to find they’d actually grown.” The fullerenes were able to absorb and incorporate carbon from the surrounding gas.
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The buckyball research results will be important for understanding fullerene formation in extraterrestrial environments. Recent reports by NASA showed that crystals of C60 are in orbit around distant suns. This suggests that fullerenes may be more common in the Universe than we thought.
“The results of our study will surely be extremely valuable in deciphering fullerene formation in extraterrestrial environments,” said FSU’s Harry Kroto, a Nobel Prize winner for the discovery of C60 and co-author of the current study.
