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  2. Abundance of the chemical elements - Wikipedia

    en.wikipedia.org/wiki/Abundance_of_the_chemical...

    The abundance of the chemical elements is a measure of the occurrences of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by mass fraction (in commercial contexts often called weight fraction), by mole fraction (fraction of atoms by numerical count, or sometimes fraction of molecules in gases), or by volume fraction.

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

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

    The Earth's crust is one "reservoir" for measurements of abundance. A reservoir is any large body to be studied as unit, like the ocean, atmosphere, mantle or crust. Different reservoirs may have different relative amounts of each element due to different chemical or mechanical processes involved in the creation of the reservoir. [1]: 18

  4. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    The atmosphere of Earth is composed of a layer of gas mixture that surrounds the Earth's planetary surface (both lands and oceans), known collectively as air, with variable quantities of suspended aerosols and particulates (which create weather features such as clouds and hazes), all retained by Earth's gravity.

  5. Oxygen - Wikipedia

    en.wikipedia.org/wiki/Oxygen

    Oxygen is the third most abundant chemical element in the universe, after hydrogen and helium. [68] About 0.9% of the Sun's mass is oxygen. [19] Oxygen constitutes 49.2% of the Earth's crust by mass [69] as part of oxide compounds such as silicon dioxide and is the most abundant element by mass in the Earth's crust.

  6. Abundances of the elements (data page) - Wikipedia

    en.wikipedia.org/wiki/Abundances_of_the_elements...

    Estimated abundance of the elements in the continental crust (C1) and in seawater near the surface (W1). The median values of reported measurements are given. Concentrations of the less abundant elements may vary with location by several orders of magnitude.

  7. Atmosphere of Venus - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Venus

    Composition of the atmosphere of Venus. The chart on the right is an expanded view of the trace elements that all together do not even make up a tenth of a percent. The atmosphere of Venus is composed of 96.5% carbon dioxide, 3.5% nitrogen, and traces of other gases, most notably sulfur dioxide. [12]

  8. Helium - Wikipedia

    en.wikipedia.org/wiki/Helium

    [132] [133] The concentration is low and fairly constant despite the continuous production of new helium because most helium in the Earth's atmosphere escapes into space by several processes. [134] [135] [136] In the Earth's heterosphere, a part of the upper atmosphere, helium and hydrogen are the most abundant elements.

  9. Natural abundance - Wikipedia

    en.wikipedia.org/wiki/Natural_abundance

    Relative abundance of elements in the Earth's upper crust In physics , natural abundance (NA) refers to the abundance of isotopes of a chemical element as naturally found on a planet . The relative atomic mass (a weighted average, weighted by mole-fraction abundance figures) of these isotopes is the atomic weight listed for the element in the ...