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Å3 = Å 3 • [1] fb-1 = fb −1 • [1] m-1 = m −1 • [1] m-2 = m −2 • [1] m-3 = m −3 • [1] km2 = km 2 • [1e6] km3 = km 3 • [1e9] µm2 = µm 2 ...
Calcium and magnesium ions present as sulfates, chlorides, carbonates and bicarbonates cause water to be hard. Water chemists measure water impurities in parts per million (ppm).
Densities using the following metric units all have exactly the same numerical value, one thousandth of the value in (kg/m 3). Liquid water has a density of about 1 kg/dm 3, making any of these SI units numerically convenient to use as most solids and liquids have densities between 0.1 and 20 kg/dm 3. kilogram per cubic decimetre (kg/dm 3)
The conversion equations depend on the temperature at which the conversion is wanted (usually about 20 to 25 °C). At an ambient sea level atmospheric pressure of 1 atm (101.325 kPa or 1.01325 bar), the general equation is:
It follows, therefore, that 1000th of a litre, known as one millilitre (1 mL), of water has a mass of about 1 g; 1000 litres of water has a mass of about 1000 kg (1 tonne or megagram). This relationship holds because the gram was originally defined as the mass of 1 mL of water; however, this definition was abandoned in 1799 because the density ...
Cholinesterase inhibition was observed at all dose levels tested, and a NOAEL of 0.03 mg/kg/day estimated by dividing a LOAEL of 0.3 mg/kg/day by an uncertainty factor of 10. As with the acute RfD, the chronic RfD of 3×10 −4 mg/kg/day was determined by dividing this NOAEL by the inter- and intraspecies uncertainty factors.
For example, the conversion factor between a mass fraction of 1 ppb and a mole fraction of 1 ppb is about 4.7 for the greenhouse gas CFC-11 in air (Molar mass of CFC-11 / Mean molar mass of air = 137.368 / 28.97 = 4.74). For volume fraction, the suffix "V" or "v" is sometimes appended to the parts-per notation (e.g. ppmV, ppbv, pptv).
An overview of ranges of mass. To help compare different orders of magnitude, the following lists describe various mass levels between 10 −67 kg and 10 52 kg. The least massive thing listed here is a graviton, and the most massive thing is the observable universe.