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  2. Plutonium - Wikipedia

    en.wikipedia.org/wiki/Plutonium

    Plutonium is the element with the highest atomic number known to occur in nature. Trace quantities arise in natural uranium deposits when uranium-238 captures neutrons emitted by decay of other uranium-238 atoms.

  3. Chemical element - Wikipedia

    en.wikipedia.org/wiki/Chemical_element

    Chemical elements may also be categorized by their origin on Earth, with the first 94 considered naturally occurring, while those with atomic numbers beyond 94 have only been produced artificially via human-made nuclear reactions. Of the 94 naturally occurring elements, 83 are considered primordial and either stable or weakly

  4. Periodic table - Wikipedia

    en.wikipedia.org/wiki/Periodic_table

    Today, 118 elements are known, the first 94 of which are known to occur naturally on Earth at present. [10] [a] The remaining 24, americium to oganesson (95–118), occur only when synthesized in laboratories. Of the 94 naturally occurring elements, 83 are primordial and 11 occur only in decay

  5. Abundance of elements in Earth's crust - Wikipedia

    en.wikipedia.org/wiki/Abundance_of_elements_in...

    The abundance of elements in Earth's crust is shown in ... 94 plutonium: Pu trace 93 ... List of chemical elements; Oklo phenomenon – Naturally occurring uranium ...

  6. List of chemical elements - Wikipedia

    en.wikipedia.org/wiki/List_of_chemical_elements

    A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...

  7. Synthetic element - Wikipedia

    en.wikipedia.org/wiki/Synthetic_element

    A synthetic element is one of 24 known chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made".

  8. Isotope - Wikipedia

    en.wikipedia.org/wiki/Isotope

    Thus, about two-thirds of stable elements occur naturally on Earth in multiple stable isotopes, with the largest number of stable isotopes for an element being ten, for tin (50 Sn). There are about 94 elements found naturally on Earth (up to plutonium inclusive), though some are detected only in very tiny amounts, such as plutonium-244.

  9. Composition of the human body - Wikipedia

    en.wikipedia.org/wiki/Composition_of_the_human_body

    Of the 94 naturally occurring chemical elements, 76 are listed in the table above. Of the remaining 18, it is not known how many occur in the human body. Most of the elements needed for life are relatively common in the Earth's crust.