enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Parts-per notation - Wikipedia

    en.wikipedia.org/wiki/Parts-per_notation

    When working with aqueous solutions, it is common to assume that the density of water is 1.00 g/mL. Therefore, it is common to equate 1 kilogram of water with 1 L of water. Consequently, 1 ppm corresponds to 1 mg/L and 1 ppb corresponds to 1 μg/L.

  3. Useful conversions and formulas for air dispersion modeling

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

    For example, such a regulation might limit the concentration of NOx to 55 ppmv in a dry combustion exhaust gas corrected to 3 volume percent O 2. As another example, a regulation might limit the concentration of particulate matter to 0.1 grain per standard cubic foot (i.e., scf) of dry exhaust gas corrected to 12 volume percent CO 2.

  4. Total dissolved solids - Wikipedia

    en.wikipedia.org/wiki/Total_dissolved_solids

    14] Water can be classified by the level of total dissolved solids (TDS) in the water: Fresh water: TDS is less than 1,000 ppm. Brackish water: TDS = 1,000 to 10,000 ppm. Saline water: TDS = 10,000 to 35,000 ppm. Hypersaline: TDS greater than 35,000 ppm. Drinking water generally has a TDS below 500 ppm.

  5. Volume fraction - Wikipedia

    en.wikipedia.org/wiki/Volume_fraction

    It is the same concept as volume percent (vol%) except that the latter is expressed with a denominator of 100, e.g., 18%. The volume fraction coincides with the volume concentration in ideal solutions where the volumes of the constituents are additive (the volume of the solution is equal to the sum of the volumes of its ingredients).

  6. Mass fraction (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Mass_fraction_(chemistry)

    Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...

  7. Air pollutant concentrations - Wikipedia

    en.wikipedia.org/wiki/Air_pollutant_concentrations

    For gases, volume percent = mole percent 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 ...

  8. Mass concentration (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Mass_concentration_(chemistry)

    The very ambiguous terms "percent solution" and "percentage solutions" with no other qualifiers, continue to occasionally be encountered. This common usage of % to mean m/v in biology is because of many biological solutions being dilute and water-based, an aqueous solution. Liquid water has a density of approximately 1 g/cm 3 (1 g/mL). Thus 100 ...

  9. Hard water - Wikipedia

    en.wikipedia.org/wiki/Hard_water

    Hardness unit conversion. 1 mmol/L 1 ppm, mg/L 1 dGH, °dH 1 gpg 1 °e, °Clark ... of CaCO 3 per Imperial gallon (4.55 litres) of water, equivalent to 14.254 ppm. A ...