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  2. Parts-per notation - Wikipedia

    en.wikipedia.org/wiki/Parts-per_notation

    Parts-per notation is often used describing dilute solutions in chemistry, for instance, the relative abundance of dissolved minerals or pollutants in water.The quantity "1 ppm" can be used for a mass fraction if a water-borne pollutant is present at one-millionth of a gram per gram of sample solution.

  3. 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 tabulated form with the estimated crustal abundance for each chemical element shown as mg/kg, or parts per million (ppm) by mass (10,000 ppm = 1%).

  4. Air pollutant concentrations - Wikipedia

    en.wikipedia.org/wiki/Air_pollutant_concentrations

    1 volume percent = 10,000 ppmv (i.e., parts per million by volume) with a million being defined as 10 6. Care must be taken with the concentrations expressed as ppbv to differentiate between the British billion which is 10 12 and the USA billion which is 10 9 (also referred to as the long scale and short scale billion, respectively).

  5. Abundance of the chemical elements - Wikipedia

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

    Parts-per-million cube of relative abundance by mass of elements in an average adult human down to 1 ppm. By mass, human cells consist of 65–90% water (H 2 O), and a significant portion of the remainder is composed of carbon-containing organic molecules. Oxygen therefore contributes a majority of a human body's mass, followed by carbon.

  6. Carbon dioxide in Earth's atmosphere - Wikipedia

    en.wikipedia.org/wiki/Carbon_dioxide_in_Earth's...

    The concentrations of carbon dioxide in the atmosphere are expressed as parts per million by volume (abbreviated as ppmv, or ppm(v), or just ppm). To convert from the usual ppmv units to ppm mass (abbreviated as ppmm, or ppm(m)), multiply by the ratio of the molar mass of CO 2 to that of air, i.e. times 1.52 (44.01 divided by 28.96).

  7. Asteroid Samples Contain Building Blocks of Life - AOL

    www.aol.com/news/asteroid-samples-contain...

    About 25% of its mass, NASA estimates, is made up of water. ... about 230 parts per million,” said NASA’s Daniel Glavin, a co-investigator on the OSIRIS-REx team. “To put that in perspective ...

  8. Useful conversions and formulas for air dispersion modeling

    en.wikipedia.org/wiki/Useful_conversions_and...

    Although ppmv and grains per dscf have been used in the above examples, concentrations such as ppbv (i.e., parts per billion by volume), volume percent, grams per dscm and many others may also be used. 1 percent by volume = 10,000 ppmv (i.e., parts per million by volume).

  9. List of Solar System objects by size - Wikipedia

    en.wikipedia.org/wiki/List_of_Solar_System...

    Parts-per-million chart of the relative mass distribution of the Solar System, each cubelet denoting 2 × 10 24 kg. This article includes a list of the most massive known objects of the Solar System and partial lists of smaller objects by observed mean radius. These lists can be sorted according to an object's radius and mass and, for the most ...