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Francium occurs naturally, although extremely rare. It can and is made in labs. Although it is considered a naturally occurring element, there is only about one ounce of it in the Earth's crust at any one time. Scientists reproduce it in labs so they can study it, ect. So little is known about Francium now; if we didn't reproduce it in labs we would know next to nothing about it.
Wiki User
∙ 12y ago
Wiki User
∙ 12y agoIn nature, uranium is found as uranium-238 (99.2742%), uranium-235 (0.7204%), and a very small amount of uranium-234 (0.0054%). Uranium decays slowly by emitting an alpha particle. The half-life of uranium-238 is about 4.47 billion years and that of uranium-235 is 704 million years,[4] making them useful in dating the age of the Earth.
Wiki User
∙ 13y agoXenon is naturally occuring. Elements which aren't natural are 104-118, 61, 43, and 93-103.
Wiki User
∙ 8y agoUranium (U) is a naturally occurring element, mainly as U-235 and U-238.
Wiki User
∙ 8y agoSome are natural while others are man-made.
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Is another word for not occur ing naturally?
manmade, manufactured, artificail
Are all the elements naturally occurring manmade or both?
Not all the elements occur naturally; some elements are man-made.
Mendelevium does it occur naturally in nature or is manmade?
Mendelevium is an artificial chemical element.
What is a naturally occuring isotope?
It is an isotope that occurs in nature, and is not manmade. Isotopes, by the way, are atoms that have the same number of protons, but different number of neutrons. The atomic number is the same, but atomic weight (or mass) is different. For instance, Carbon can be Carbon 10, 11, 12, or 14. They are all carbon.
Does steel occur naturally?
no, steel is one of many manmade alloys. the closest natural material to steel are nickel-iron meteorites.
Is another word for not occur ing naturally?
manmade, manufactured, artificail
What is a artificial?
Artificial means that it does not occur naturally. If something is artificial it is manmade.
Is ammonia manmade?
Ammonia does occur naturally, but it is manufactured on an industrial scale.
Are all the elements naturally occurring manmade or both?
Not all the elements occur naturally; some elements are man-made.
Does a radioisotope of gold occur naturally?
No, gold has only one naturally occurring isotope and it is non-radioactive.
Mendelevium does it occur naturally in nature or is manmade?
Mendelevium is an artificial chemical element.
What is the use of isotope of oxygen?
The isotopes are not manufactured for specific uses, they occur in nature naturally.
What is a naturally occuring isotope?
It is an isotope that occurs in nature, and is not manmade. Isotopes, by the way, are atoms that have the same number of protons, but different number of neutrons. The atomic number is the same, but atomic weight (or mass) is different. For instance, Carbon can be Carbon 10, 11, 12, or 14. They are all carbon.
Does steel occur naturally?
no, steel is one of many manmade alloys. the closest natural material to steel are nickel-iron meteorites.
Does samarium - 153 occurs naturally or is produced synthetically?
This isotope does not occur in the environment and thus must be produced synthetically.
Is zinc manmade or naturally occurring?
Both. Zinc can be found in nature and also can be manmade.
Are minerals manmade?
No. By definition a mineral is naturally occurring.
