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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.
Lead's per-particle abundance in the Solar System is 0.121 ppb (parts per billion). [100] [k] This figure is two and a half times higher than that of platinum, eight times more than mercury, and seventeen times more than gold. [100]
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).
Ground-level ozone (O 3), also known as surface-level ozone and tropospheric ozone, is a trace gas in the troposphere (the lowest level of the Earth's atmosphere), with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas.
It is expressed in terms of nano-grams (ng), pico-grams (pg) or femto-grams (fg) with fg being better than pg better than ng. It can also be expressed in terms of parts per billion (ppb), parts per trillion (ppt) or parts per quadrillion (ppq). Sensitivity is important because most explosives have a low vapor pressure .
Firefighters explained that winds carried embers through attic vents, setting homes aflame almost at random Ethan Swope—AP. ... or three parts per billion higher than in 2023. Said Laurence ...
Walmart recalled the Great Value apple juice for containing inorganic arsenic levels of 13.2 parts per billion (ppb), which is above the 10 ppb considered safe by the FDA.
ISO 3696 (Water for analytical laboratory use) specifies a purity of ten parts per billion, or 10×10 −9 ― this water cannot be kept in glass or plastic containers as they leach impurities into the water, and glassware must be washed with hydrofluoric acid before use. Ten parts per billion is equivalent to a homeopathic dilution of 4C.