Which electrode for which titration?
Titrant | Specifics | Electrode description* | Order No. | Reference Electrolyte | Remarks |
Aqueous acid/bases | Ecotrode Plus | 6.0262.100 | c(KCl) = 3 mol/L 6.2308.020 | ||
alkaline samples | Unitrode | 6.0259.100 | c(KCl) = 3 mol/L | ||
titrations performed at high temperatures | Unitrode | 6.0259.100 | Idrolyte | ||
titrations with small sample volumes | Combined LL micro pH glass electrode OR Combined flat membrane pH glass electrode | 6.0234.100
| 6.2308.020 | Shaft diameter 6.4 mm, minimal immersion depth; 10 mm Shaft diameter 12 mm, minimal immersion depth; 1–2 mm | |
titrations in water with low conductivity | Aquatrode plus | 6.0257.000 | 6.2308.020 | Typical application: water analysis - p&m value etc. | |
Perchloric acid | See AB 80 and Monograph"Non-aqueous titration of acids and bases with potentiometric endpoint indication" | Solvotrode - combined LL pH glass electrode, ground-joint diaphragm (PCTFE) | 6.0229.100 | c(LiCl) = 2 mol/L in ethanol 6.2312.010 | easy to clean sleeve diaphragm IMPORTANT: When not in daily use, store in LiCI sat. in ethanol and soak membrane in distilled water before use. However, when in daily use, store in distilled water, so that only the membrane is immersed, not the diaphragm. Before the measurement lift the diaphragm sleeve slightly and allow a small amount of electrolyte to flow out. Rinse the electrode with distilled water, replenish the reference electrolyte and start the titration (see bottom of chart). IMPORTANT: Never fill the Solvotrode with LiCIO4 in glacial acetic acid! |
TBAOH | See AB 80 and Monograph"Non-aqueous titration of acids and bases with potentiometric endpoint indication" | Solvotrode - combined LL pH glass electrode, ground-joint diaphragm (PCTFE) | 6.0229.100 | c(TEABr) = 0.4 mol/L in ethylen glycol1 6.2320.000 | |
Potassium methylate | Solvotrode - combined LL pH glass electrode, ground-joint diaphragm (PCTFE) | 6.0229.100 | c(TEABr) = 0.4 mol/L in ethylen glycol1 | ||
Cyclohexyl-amine | Solvotrode - combined LL pH glass electrode, ground-joint diaphragm (PCTFE) | 6.0229.100 | c(LiCl) = 2 mol/L in ethanol 6.2312.010 | ||
Silver nitrate | AB 25 | Ag-Titrode, possibly Ag2S coated | 6.0430.100 | ||
arsenite, cerium sulphate, iron (III), iodine, potassium bromate, sodium nitrite, sodium thiosulphate, oxalic acid, permanganate, titanium | For titrations where the pH value during the titration doesn't change. | Pt-Titrode | 6.0431.100 | Electrode is also available with a plug-in head S (6.0431.500 ) | |
For titrations during which the pH value changes. | Combined LL Pt-ring electrode | 6.0451.100 | 6.2308.020 | ||
Karl Fisher reagent | 6.0338.100 | ||||
Cr3+ , Fe2+, | Also for COD titrations | Micro Au-Titrode | 6.0435.110 | L = 160 mm, Loger version available: (6.9904.023), L= 250 mm | |
EDTA | Back-titration of the BaCl2 excess. For sulphate determination see AB 140. | Polymer membrane electrode, Ca2+ | 6.0508.110 | 6.2308.020 | a separate reference electrode is needed. |
EDTAComplexon® III and IV | Determination of Al, Ba, Ca, Cd, Bi, Co, Fe, Mg, Ni, Pb, Zn. See AB 125 | 6.0502.140 | 6.2308.020 | a separate reference electrode is needed. Order no: 6.0750.100 | |
Determination of Ca, Mg, See AB 125 | 6.0508.110 | ||||
Surfactants in aqueous media | Tego® trant A 100,2 | Ionic surfactant electrode | 6.0507.120 | 6.2308.020 | a separate reference electrode is needed. |
sodium lauryl sulphate, see AB 233 | «Cationic surfactant» electrode | 6.0507.150 | 6.2308.020 | a separate reference electrode is needed. Order No: 6.0726.100 | |
Sodium tetra phenyl borate, see AB 230, AB 263 | NIO surfactant electrode | 6.0507.010 | Inner chamber of the reference electrode: | a separate reference electrode is needed. | |
Non aqueous surfactants | Nonaqueous media, solvents as Chloroform, MIKB, see AB 269 | Surfactrode resistant | 6.0507.130 | 6.2308.020 | a separate reference electrode is needed. electrode not suitable for high salt concentrations and pH > 10 |
Nonaqueous media, solvents as MIKB Two phase titration, see AB 269 | Surfactrode refill | 6.0507.140 | 6.2308.020 | a separate reference electrode is needed. electrode not suitable for Chloroform | |
AB = Application Bulletin * All these electodes are equipped with a Metrohm plub-in head G3 1) TEABr 0.4 mol/L tetra ethyl ammonium bromide in ethylene glycol (6.2320.000) is an electrolyte solution for non-aqueous titrations. It is very useful when titrating low acid contents with TBAOH. In such cases the LiCI sat. in ethanol (6.2312.000) would cause an alkali error during the measurement. The Solvotrode is a combined pH glass electrode specially designed for non-aqueous titrations. This electrode is normally filled with LiCI sat. in ethanol. However, when titrating with TBAOH we strongly recommend replacing the CiCI electrolyte with 0.4 mol/L TEABr in ethylene glycol. This electrolyte can of course also be used for all other non-aqueous titrations with various titrants. 2) TEGO trant A 100 3 To connect an electrode with plug-in head G to a Titrino or 726/796 Titroprocessor, use one of the following cables: 6.2104.020 (1 m), 6.2104.030 (2 m) or 6.2104.040 (3 m); to connect an electrode an electrode with plug-in head S to the above instruments, use cable 6.2104.510 (1 m). See Metrosensor Electrode Catalog for additional information. Storage of the Solvotrode when not in daily use: Store the Solvotrode in LiCI sat. in ethanol. Use a normal electrode holder. More information on Electrodes> See also: which electrode for which application? |
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