Asked in ScienceTechnologySelenium
What is the rarest naturally occurring element on earth?
September 15, 2011 10:04AM
According to sources, Astatine (At) is the rarest naturally occurring element, roughy 25 grams are in the earth's crust at any given time. It has a half-life of only 8.3 hours.
A single solid element or compound occurring naturally in the earth crust?
Asked in Physics
Which element is the heaviest actininde that occurs naturally on earth?
How many naturally occurring elements are on earth?
What are naturally occurring compounds in the earth called?
What is a naturally occuring isotope?
deuterium is a naturally occurring isotope of hydrogen. iodine is the only naturally occurring isotope of iodine. gold is the only naturally occurring isotope of gold. radium-e is a naturally occurring radioisotope of bismuth. orealloy is a naturally occurring fissile radioisotope of uranium. depletalloy is a naturally occurring nonfissile radioisotope of uranium. A naturally occurring isotope is any stable or radioactive isotope of an element that is on earth now by natural processes. If the isotope is radioactive either its halflife must be long enough for it to have survived since the earth's formation or be replenished by the natural decay of other radioisotopes. If the naturally occurring isotope is not the only naturally occurring isotopee of that element then elemental separation will be required to isolate (e.g., deuterium from natural hydrogen, orealloy and depletalloy from natural uranium).
Asked in Science, Chemistry, Elements and Compounds
What is the least common element in the world?
Astatine is the rarest naturally-occurring element, with the total amount in Earth's crust estimated to be less than 1 oz (28 g) at any given time. This amounts to less than one teaspoon of the element. Guinness World Records has dubbed the element the rarest on Earth, stating: "Only around 0.9 oz (25 g) of the element astatine (At) occurring naturally". Isaac Asimov, in a 1957 essay on large numbers, scientific notation, and the size of the atom, wrote that in "all of North and South America to a depth of ten miles", the number of astatine atoms at any time is "only a trillion".
Asked in Chemistry, Science Experiments
How is astatine producedwhat element is it most similar to?
Asked in Science
Is carbon monoxide naturally occurring or is it manmade?
Asked in Diamonds
Other than diamond hardest naturally occurring substance?
Asked in Chemistry, Periodic Table
What element is naturally found on earth but is labeled as a laboratory made element on the periodic table?