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Why are technetium neptunium and promethium considered natural elements even though they are not found on earth?
Wiki User
∙ 10y ago
In the last years technetium, prometium, neptunium and plutonium was found in the nature but in extremely low concentrations.
Because they are found in the universe. They have been observed in the spectrum of certain stars.
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∙ 10y ago
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How many natural occurring elements are there?
9290, technetium and promethium are radioactive with short halflives, they do not occur naturally.Of the 118 elements that are known, 94 occur naturally. The elements that do not occur on earth naturally, have been produced artificially. Some of the elements that do not occur on earth naturally have been detected in other parts of the universe. See link for more information.Tc and Pm of number 1-92 had not been found naturally until fairly recently, but now they have. Promethium, technetium, neptunium and plutonium are now considered natural chemical elements as trace quantities have been found in nature; consequently, 94 natural chemical elements.We know today there are 118 elements total. So far.94 are considered natural elements as we can add promethium, plutonium and neptunium to natural elements because these elements exist in nature in ultratiny trace quantities.About thirty native elements are known to occur naturally, by themselves, in pure form, uncombined with other elements into minerals. They include metals like copper, gold, lead, and iron; semi-metals like antimony, arsenic, bismuth, and tellurium, and non-metals like diamond, sulfur, and selenium.Some elements decay into other elements very quickly and very little of them remain. However they can be produced in laboratories and during supernova explosions.90, technetium and promethium are radioactive with short halflives, they do not occur naturally.Astatine has an even shorter half life, being furiously radioactive. Make it 89 ?90 elements out of the first 92 elements are naturally occurringThere are 88 naturally-occurring chemical elements90, technetium and promethium are radioactive with short halflives, they do not occur naturally.98
How many elements occur natural?
Elements 1-92 except 43 (technetium) and 61 (promethium) occur naturally. So, there are 90 naturally occurring elements.
What elements are radioactive?
Answerelements with a nonstable isotope or at least one naturally occurring isotope that is radioactive. AnswerAll elements have radioactive isotopes.There are a lot of radioactive elements: Technetium, Promethium, Polonium, Astatine, Radon, Francium...Here is the whole list: http://periodictable.com/Elements/Radioactive
Why does the periodic table have over 110 elements when only 90 occur naturally on Earth?
The periodic table lists all elements that are possible, i.e. those with an integral number of protons in the nucleus of its atoms.Some of these are extremely rare, at least on Earth, such as technetium (43), promethium (61), neptunium (93), and plutonium (94). Others, mostly radioactive isotopes with more than 83 protons, have not been found anywhere on Earth, but can be synthesized using nuclear collisions between other elements. So far, all but five or six of the 118 have been named, having been created or observed for at least a few atoms.
Which element is radioactive and synthetic?
All transuranic elements are synthetic and radioactive.
What are elements that are made in laboratory?
Manmade elements. These have traditionally been considered to be: Technetium, Promethium, Neptunium, and all elements beyond Neptunium. However trace levels of several of these have since then been detected naturally.
Are there any elements lighter than Uranium that do not occur naturally?
In the past promethium and technetium were considered as artificial elements; now extreme traces of these elements were discovered in the nature.
All of what element's isotopes are radioactive?
Technetium, Promethium, and all elements heavier than Bismuth.
How many elements are natural in the periodic table?
90: The first 92 elements except technetium and promethium.
How many elements in the periodic table natural?
90: The first 92 elements except technetium and promethium.
Why are technetum promethium and neptunium considered naturally occurring elements even though they are not found on earth?
These elements exist also naturally - in infinitesimal amounts - in the Earth crust.But practically are artificial elements.
What element are all of radioactive all?
Technetium, Promethium, and all elements heavier than Bismuth.
What two 'light' elements have no stable nonradioactive isotopes?
The two elements are elements 43, Tc, technetium, and 61, Pm, promethium. Technetium has a few "nearly stable" isotopes with half-lives of over a million years. Promethium's longest lived isotope has a half-life of about 20 years.
What are two synthetic elements with atomic numbers less than 92?
Technetium, Tc, and promethium, Pm
Find one element on the chart that has no stable isotopes?
Technetium, Promethium, and all elements heavier then Bismuth.
Give the names of naturally occurring elements?
In the attached list manmade elements are: technetium, promethium and the elements with atomic number between 94 and 118.
What group on the periodic table are synthetic elments?
Technetium (43), Promethium (61), and all the transuranic elements are synthetic.
