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Ppb

Elemental fluorine and the fluoride ion are highly toxic. The free element has a characteristic pungent odor, detectable in concentrations as low as 20 ppb, which is below the safe working level. The recommended maximum allowable concentration for a daily 8-hour time-weighted exposure is 1 ppm. [Pg.24]

Parts per million (ppm) and parts per billion (ppb) are mass ratios of grams of solute to one million or one billion grams of sample, respectively. For example, a steel that is 450 ppm in Mn contains 450 pg of Mn for every gram of steel. If we approximate the density of an aqueous solution as 1.00 g/mL, then solution concentrations can be expressed in parts per million or parts per billion using the following relationships. [Pg.18]

Nanograms of solute per gram of solution for aqueous solutions the units are often expressed as micrograms of solute per liter of solution (ppb). [Pg.18]

A certain concentration method works best when the analyte s concentration is approximately 10 ppb. [Pg.51]

A spectrophotometric method for the quantitative determination of Pb + levels in blood yields an Sjtand of 0.474 for a standard whose concentration of lead is 1.75 ppb. How many parts per billion of Pb + occur in a sample of blood if Ssamp is 0.361 ... [Pg.109]

A third spectrophotometric method for the quantitative determination of the concentration of in blood yields an Sjamp of 0.193 for a 1.00-mL sample of blood that has been diluted to 5.00 mb. A second 1.00-mL sample is spiked with 1.00 )J,L of a 1560-ppb Pb + standard and diluted to 5.00 mb, yielding an Sspike of 0.419. Determine the concentration of Pb + in the original sample of blood. [Pg.112]

A fifth spectrophotometric method for the quantitative determination of the concentration of Pb + in blood uses a multiple-point standard addition based on equation 5.6. The original blood sample has a volume of 1.00 mb, and the standard used for spiking the sample has a concentration of 1560 ppb Pb +. All samples were diluted to 5.00 mb before measuring the signal. A calibration curve of Sjpike versus Vj is described by... [Pg.114]

A sixth spectrophotometric method for the quantitative determination of Pb + levels in blood uses CQ+ as an internal standard. A standard containing 1.75 ppb Pb + and 2.25 ppb CQ+ yields a ratio of Sa/Sis of 2.37. A sample of blood is spiked with the same concentration of Cu +, giving a signal ratio of 1.80. Determine the concentration of Pb + in the sample of blood. [Pg.116]

To determine the concentration of analyte in a sample, a standard additions was performed. A 5.00-mL portion of the sample was analyzed and then successive 0.10-mL spikes of a 600.0-ppb standard of the analyte... [Pg.131]

X f0 ppb Sb was added, anodic stripping voltammetry is repeated, giving a peak current of f.i4 pA. How many nanograms of Sb is collected from the individual s hand ... [Pg.538]

Trihalomethane (ppb) Peak Area solution of terpene hydrate in a 25-mL volumetric flask and... [Pg.616]

See other pages where Ppb is mentioned: [Pg.495]    [Pg.1440]    [Pg.155]    [Pg.16]    [Pg.18]    [Pg.50]    [Pg.51]    [Pg.109]    [Pg.109]    [Pg.109]    [Pg.109]    [Pg.110]    [Pg.110]    [Pg.110]    [Pg.110]    [Pg.112]    [Pg.112]    [Pg.112]    [Pg.112]    [Pg.113]    [Pg.113]    [Pg.113]    [Pg.115]    [Pg.115]    [Pg.117]    [Pg.117]    [Pg.117]    [Pg.117]    [Pg.417]    [Pg.417]    [Pg.417]    [Pg.432]    [Pg.437]    [Pg.456]    [Pg.456]    [Pg.456]    [Pg.523]    [Pg.538]    [Pg.539]   
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See also in sourсe #XX -- [ Pg.642 ]



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Percentage, ppm, and ppb

Ppb, parts per billion

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