does anyone know about the element chromium?
926079
Apparently several people do since it has been widely used commercially for at least a year or so.
300254
None of them.  \nTechnetium has been observed both in spectral star signatures, and in very small quantities in pitchblende.  To quote from Wickepedia "In 1962, technetium-99 was isolated and identified in pitchblende from the Belgian Congo in very small quantities (about 0.2 ng/kg); there it originates as a spontaneous fission product of uranium-238. This discovery was made by B.T. Kenna and P.K. Kuroda."
517542
Since all the numbers are filled in on the chart, and the transuranium elements are all man-made and fairly unstable, I think we're probably out of surprises as far as elements are concerned.  I say "probably" to cover my açç, as any good scientist does.  Who really knows what sπτt's going down in the core of the galaxy, for instance. \n\nAs far as *compounds* go, there's still lots and lots of wild and wacky stuff to be found.  What time does the Mother Ship leave, anybody know?
1054743
A major research institution has recently announced the discovery of the heaviest element yet known to science. This new element has been tentatively named "Administratium." Administratium has 1 neutron, 12 assistant neutrons, 75 deputy neutrons, and 111 assistant deputy neutrons, giving it an atomic mass of 312.\n\nLightest would be Hydrogen.\n\nelements consist of atoms which have protons, neutrons and electrons.
1116812
The paper cited below says "It is the rarest element with an amount of only 550 g. in the entire earth's crust,"\n\nThat's a little more than 18 atoms.
719042
Dichromate ion is: Cr2072-.\n \nhybrid state is:sp3d.\none lp on each Cr atom\n4 pi bonds\n2 0- so overall charge is 2-\nstructure not possible to be shown here.\nBye
864183
Not to my knowledge but you could be the first to prepare one.  Remember that some elements are toxic in a few but not all of their oxidation states.\n\nI guess you could surmise that toxicity is somewhat correlated to abundance but that is not always the case and I would not stake my life on it.  The example you give of water and barium is not a good one because water is not an element.  Lead is way more abundant than gold but lead is toxic and gold is not.  And, as you point out, the dose makes the poison.\n\nBut there is a very rough inverse relationship in nature between an element's abundance and its toxicity.  In my view, another excellent building block for the Theory of Evolution.  That is, organisms would evolve using the most abundant substances or, at least tolerating them, leaving them susceptible to rarer substances that may interfere with processes developed to use or withstand the common stuff.
924016
Hey,\nI know a little about zinc. But I thought these two sites might help you\n\nhttp://ergosphere.blogspot.com/2005/06/zinc-miracle-metal.html\n\nhttp://www.ctds.info/zinc1.html\n\nHave fun
739924
try here:http://rds.yahoo.com/_ylt=A0oGkjr5altFbCIATYFXNyoA;_ylu=X3oDMTE2aWNrczNxBGNvbG8DdwRsA1dTMQRwb3MDOARzZWMDc3IEdnRpZANERlg1XzMw/SIG=12odtnv12/EXP=1163705465/**http%3a//www.theodoregray.com/PeriodicTable/Elements/013/index.s7.html
782015
The MOST recently discovered element was atomic number 118.  It is being temporarily called 'ununoctium'.  As to WHEN it was discovered... that's a little more complicated.\n\nA team of element-makers at Lawrence Berkeley lab claimed to have made it in 1999, but when nobody could reproduce the find with the lab's methods (even the original lab), their finding was discredited.\n\nIn Spring of 2002 (it took four months) the Joint Institude of Nuclear Research in Dubna claimed to have produced an atom of ununoctium.  This was confirmed by Dubna and the Berkeley lab when each of them produced another atom in 2005.\n\nThe average lifespan of these three atoms was just under a thousandth of a second.  So don't expect any accumulation of the stuff!
329771
YES it is a heavy metal.  \n\nIron is a chemical element with the symbol Fe (L.: Ferrum) and atomic number 26. Iron is a group 8 and period 4 metal. Iron is notable for being the final element produced by stellar nucleosynthesis, and thus the heaviest element which does not require a supernova or similarly cataclysmic event for its formation. It is therefore the most abundant heavy metal in the universe.
56554
While I don't particularly feel like doing the work for you, this site gives information on why all of the elements are named as they are.\n\nhttp://www.ktf-split.hr/periodni/en/
2825
Most of the elements have been either discovered by scientists or created by scientists.  Only a choice few have been known since antiquity -- usually ones that are found in their elemental state in nature or are easy to isolate from compounds (usually ores).  These are iron, copper, tin, lead, silver, gold, and mercury.  \n\nSome of the elements were discovered by people you might not consider scientists.  For example, Albertus Magnus was the first to isolate arsenic.  He was a theologian and philosopher in the 13th century, but also researched alchemy, long before true "scientific" methods were established -- would you count arsenic as being discovered by a scientist?  It's kind of a gray area.
454489
i do not know about an element but u do get dyes which will emit in the wavelengths u mentioned if excited by UV.
545668
"The element was actually discovered by Perrier and Segre in Italy in\n1937. It was found in a sample of molybdenum, which was bombarded by\ndeuterons in the Berkeley cyclotron, and which E. Lawrence sent to\nthese investigators. Technetium was the first element to be produced\nartificially. Since its discovery, searches for the element in\nterrestrial material have been made without success. If it does exist,\nthe concentration must be very small."\n\nTellurium, a metalloid, which can be found in group 7A was first discovered by German scientist Franz Joseph Muller von Reichenstien, but was recognized 16 years later in 1798 as a element and given its name by the German chemist Martin Heinrich Klaproth. Tellurium ranks about 78th in natural abundance. It occurs in the pure state or is found in combination with gold, silver, copper, lead, and nickel in such minerals as sylvanite, petzite, and tetradymite. Tellurium meltsa about 452 degrees C, boils about 1390 degrees C, and has a specific gravity of 6.25. Tellurium is one of the rareest elements. Its compunds are toxic, and the element itself plays no known role in living organisms. Tellurium is used in manufacturing rectifiers and thermoelectric devices. It is employed as a vulcanizing agent in the processing of natural and synthetic rubber.
854963
Check out this website it will tell you all you would ever want to know about radon and any other element.\n\nhttp://www.lenntech.com/Periodic-chart-elements/Rn-en.htm
112289
Information for all of the elements is given at the Wikipedia. Linked below is the article for carbon, with everything you asked for.\n\nTo see similar information for a different element, change the word "Carbon" in the URL to another element.