IUPAC - gravimetric factor (09044)

gravimetric factor

symbol:

g_{F}

abbreviation: GF

https://doi.org/10.1351/goldbook.09044

Mass fraction of analyte in a precipitate (see precipitation) obtained in a gravimetric analysis.

Notes:

Gravimetric factor is calculated by $g_{F} = (M_{A} v_{A}) / (M_{P} v_{P})$ , where $M_{A}$ , $M_{P}$ are molar masses of analyte and precipitate, respectively, and $v_{A}$ and $v_{P}$ are the stoichiometric numbers in the precipitation reaction.
Historically, the gravimetric factor is given the initialism GF, but to conform to the IUPAC convention that quantities should have a single symbol, it is recommended that $g_{F}$ is used in equations.
The gravimetric factor is used to calculate the mass fraction of an analyte in a sample ( $w$ ) by $w = m_{P} / m_{s a m p l e} \times g_{F}$ , where $m_{P}$ is the mass of precipitate and $m_{s a m p l e}$ the mass of sample.

Examples:

Sulfur trioxide ( $M (SO_{3}) = 80.0640 g {mol}^{- 1}$ ) is precipitated as barium sulfate ( $M (BaSO_{4}) = 233.390 g {mol}^{- 1}$ ), $1 mol$ $SO_{3}$ becomes $1 mol$ $BaSO_{4}$ . Therefore, $g_{F} = 80.0640 / 233.390 = 0.343048$ .
Disilver oxide ( $M (Ag_{2} O) = 231.736 g {mol}^{- 1}$ ) is dissolved and precipitated as silver chloride ( $M (AgCl) = 143.321 g {mol}^{- 1}$ ), $1 mol$ of $Ag_{2} O$ becomes $2 mol$ $AgCl$ . Therefore, $g_{F} = ½ (231.736 / 143.321) = 0.808451$ .

Source:
PAC, 2025, 97, 137. (Glossary of terms for mass and volume in analytical chemistry (IUPAC Recommendations 2024)) on page 4 [Terms] [Paper]

Citation: 'gravimetric factor' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.09044 RIS BibTex EndNote

Div. Text XML JSON

Alphabetical Index

Additional Indexes

Version 3.0.1 (7517 Terms)

gravimetric factor