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Short answer
Gravimetric titration is a titration in which the amount of titrant delivered is measured by mass on a balance instead of by volume on a burette. The chemistry, the endpoint and the calculation logic are the same as in a volumetric titration. What changes is the measuring instrument, and with it the concentration unit (mol/kg rather than mol/L) and the uncertainty budget. It is not the same thing as gravimetric analysis, where a precipitate is weighed.
Definition and scope
In a conventional titration, a burette reads the volume of titrant added until an endpoint is detected by an indicator or an electrode. In a gravimetric titration, the titrant is weighed: a bottle or syringe of titrant is weighed before and after each addition, or the analyte vessel sits on a balance while titrant is added and the mass is recorded. The endpoint mass then replaces the endpoint volume in the calculation.
Because mass does not change with temperature the way a liquid’s volume does, titrant concentration is naturally expressed per kilogram of solution. A peer-reviewed comparison of acid-base titration techniques prepared its sodium hydroxide titrant gravimetrically at 0.05 mol/kg and, as the authors put it, favoured gravimetric methods for a shorter traceability chain and lower uncertainties.
Gravimetric titration belongs to the same family as the burette work described in our guide to analytical chemistry; it changes how the titrant is measured, not what is being measured.
How it is done in practice
The published setups differ mainly in what sits on the balance and how fine the balance reading is. The table sets out the arrangements described in the sources cited at the end of this page.
| Arrangement | What is measured | Instrument detail reported | Source |
|---|---|---|---|
| Volumetric (reference method) | Titrant volume from a burette | 25 mL burette, 0.05 mL resolution | Morales-Erazo et al., 2019 |
| Gravimetric, mode 1 | Beaker of analyte on a balance; titrant added by a manual dispenser; mass recorded at each addition together with pH | Balance reading to 0.1 mg | Morales-Erazo et al., 2019 |
| Gravimetric, mode 2 | Titrant in a dropper bottle weighed before and after each addition (mass by difference) | Balance reading to 0.01 g | Morales-Erazo et al., 2019 |
| Teaching-lab gravimetric | Controlled-drop squeeze bottle (60 mL) weighed before and after, in place of a 50 mL burette | Two-decimal-place balance | University of Waterloo, Chem 13 News |
In the 2019 study the titrant was standardised against a potassium hydrogen phthalate (KHP) certified reference material, using about 0.2 g of KHP dissolved in about 130 mL of type I water, with phenolphthalein, a pH electrode and a conductivity cell as endpoint detectors. The test sample was 50 g of a hydrochloric acid solution. The Waterloo article describes the same idea at teaching scale: juice samples titrated with approximately 0.1 M sodium hydroxide. Eight students took part, working in pairs, and the best set of results from one pair gave six trials with a mean titration mass of 2.67 g and a 95% confidence interval of 2.63 to 2.72 g. The article notes that those masses are approximate because the sodium hydroxide was not standardised. Separately, it states that the gravimetric method needs just less than half the sample amount to give the same precision as the volumetric method in a KHP standardisation; it gives no figures for that comparison.
What the evidence says about uncertainty
The most useful single finding for a lab deciding between the two modes is quantitative. In the 2019 paper, which evaluated bias following ISO 33:2015, uncertainty decreased by about 40% when gravimetric rather than volumetric titration was used. The same study found that how the endpoint is detected matters as much as how the titrant is measured: potentiometric detection gave the lowest uncertainties, while conductometric detection showed bias up to 78 times larger. The best metrological characteristics, meaning the lowest bias and uncertainty, came from gravimetric titration combined with potentiometric endpoint detection. A gravimetric dispenser on its own does not rescue a poor endpoint signal.
Related methods and how they differ
Volumetric titration
The default bench method: a calibrated burette delivers titrant and a volume is read. Its accuracy depends on burette calibration and temperature; see types of laboratory glassware for how burettes and other volumetric glassware are classed.
Gravimetric analysis
Gravimetric analysis determines an analyte by forming a precipitate (or other solid), isolating it and weighing it. There is no titrant and no endpoint. The shared word “gravimetric” refers only to the use of a balance.
Thermogravimetric analysis
Thermogravimetric analysis records a sample’s mass as it is heated or held at a temperature. It characterises a solid sample and does not involve titrant delivery.
Coulometric titration
In coulometric titration the titrant is generated electrically and the amount is calculated from charge. NIST used coulometric titration (30 titrations) to assign the certified value of its potassium hydrogen phthalate acidimetric standard, SRM 84L.
Where it matters for labs
Standardisation still depends on the reference material
Weighing the titrant does not remove the need for a trustworthy standard. NIST’s certificate for SRM 84L (issued 5 February 2024, valid until 1 April 2029) certifies KHP at a mass fraction of 99.9934% with an expanded uncertainty of 0.0076% (k = 2.04) and states traceability to the SI. The certificate also says the certified value is attained only if its handling procedure is followed: grind the material for 60 to 90 seconds in an agate mortar, dry it at 120 degrees C for 2 hours and store it in a desiccator over anhydrous magnesium perchlorate. Test portions under 300 mg are not recommended because of inhomogeneity, and dried but unground portions gave 99.94% to 99.99% because of occluded water. The material is certified for acidimetric assay only and is not intended as a pH standard.
Equipment a gravimetric setup relies on
From the setups above, a gravimetric titration needs an analytical balance with enough resolution (0.1 mg or 0.01 g in the cited work), a way to deliver titrant in controlled amounts (a manual dispenser or controlled-drop bottle), an endpoint detector such as a pH meter or indicator, and a titration vessel such as an Erlenmeyer flask or beaker. Where an acid-base endpoint is read from a titration curve, our explainer on the half-titration point shows how that curve is interpreted.
Common misunderstandings
- “It is the same as gravimetric analysis.” It is not. Gravimetric analysis weighs a precipitate; gravimetric titration weighs the titrant delivered.
- “It changes the chemistry.” The reaction and endpoint are the same. Only the measurement of the amount of titrant differs.
- “A balance guarantees a better result.” In the 2019 study the endpoint detection method changed bias by up to 78 times, so the detection method must be judged alongside the dispensing mode.
- “Mass-based titrant concentration needs no standardisation.” The titrant in that study was still standardised against a KHP certified reference material.
FAQ
Is gravimetric titration more accurate than volumetric titration?
In one peer-reviewed comparison the uncertainty was about 40% lower with gravimetric titration, with the best result when paired with potentiometric endpoint detection. That is evidence from a single study and setup, not a universal guarantee.
Does gravimetric titration need a burette?
No. The setups described above use a manual dispenser or a weighed dropper bottle in place of a burette, with a balance recording the mass delivered.
What unit is used for concentration?
Mass-based work naturally uses amount of substance per kilogram, for example the 0.05 mol/kg sodium hydroxide titrant in the 2019 study.
Is gravimetric titration the same as gravimetric analysis?
No. Gravimetric analysis weighs a precipitate or other isolated solid; gravimetric titration weighs the titrant delivered to reach an endpoint.
Sources
- Morales-Erazo L, Gonzalez-Cardenas I, Abella-Gamba J, et al. Tecnicas de titulacion acido-base: consideraciones metrologicas. Revista Colombiana de Quimica 48(1), 2019 (Universidad Nacional de Colombia). https://www.redalyc.org/journal/3090/309058491010/309058491010.pdf. Date checked: 29 October 2026.
- National Institute of Standards and Technology. Certificate of Analysis, Standard Reference Material 84L, Potassium Hydrogen Phthalate, issued 5 February 2024. https://tsapps.nist.gov/srmext/certificates/84l.pdf. Date checked: 29 October 2026.
- University of Waterloo, Centre for Advancing Science Education. Gravimetric titration: simple, buret-free and high precision (Chem 13 News). https://uwaterloo.ca/centre-advanced-science-education/news/gravimetric-titration-simple-buret-free-and-high-precision. Date checked: 29 October 2026.
