Which electrode for which Titration, Application Bulletin Metrohm

Which electrode for which Titration? Titrant Specifics Electrode description* Cat. No./ Order No. Reference Electrolyte Remarks Aqueous acid/bases Combined LL pH glass electrode 020912146 (6.0232.100) c(KCl) = 3 mol/L 020096101 (6.2308.020) alkaline samples Combined LL pH glass electrode, U glass 020912162 (6.0222.100) c(KCl) = 3 mol/L 020096101 (6.2308.020) titrations performed at high temperatures Unitrode 020910674 (6.0259.100) c(KCl) = 3 mol/L 020096101 (6.2308.020) titrations with small sample volumes Combined LL micro pH glass electrode OR Combined flat membrane pH glass electrode 020912235 (6.0234.100) 020915617 (6.0227.100) c(KCl) = 3 mol/L 020096101 (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 020910631 (6.0252.300) c(KCl) = 3 mol/L 020096101 (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) 020910551 (6.0229.100) c(LiCl) = 2 mol/L in Ethanol 020094435 (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) 020910551 (6.0229.100) c(TEABr) = 0.4 mol/L in ethylen glycol1 020094451 (6.2320.000) Potassium methylate Solvotrode - combined LL pH glass electrode, ground-joint diaphragm (PCTFE) 020910551 (6.0229.100) c(TEABr) = 0.4 mol/L in ethylen glycol1 020094451 (6.2320.000) Cyclohexyl-amine Solvotrode - combined LL pH glass electrode, ground-joint diaphragm (PCTFE) 020910551 (6.0229.100) saturated LiCl in Ethanol 020094443 (6.2312.000) Silver nitrate AB 25 Ag-Titrode, possibly Ag2S coated 6.0430.100 Electrode is also available with a plug-in head S: 20 94 852-3 (6.0430.500)3 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: 20 94 852-3 (6.0431.500)3 For titrations during which the pH value changes. Combined LL Pt-ring electrode 6.0451.100 c(KCl) = 3 mol/L 020096101 (6.2308.020) Karl-Fisher reagent Double Pt-wire electrode 020928841 (6.0338.100) Cr3+ , Fe2+, Also for COD titrations Micro Au-Titrode 020948604 (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+ 020955856 (6.0508.110) c(KCl) = 3 mol/L 020096101 (6.2308.020) a separate reference electrode is needed. Order no: 20 94 411-1 (6.0726.107) EDTA Complexon® III and IV Determination of Al, Ba, Ca, Cd, Bi, Co, Fe, Mg, Ni, Pb, Zn. See AB 125 Ion selective electrode Cu2+ 020959002 (6.0502.140) c(KCl) = 3 mol/L 020096101 (6.2308.020) a separate reference electrode is needed. Order no: 20 94 411-1 (6.0726.107) Determination of Ca, Mg, See AB 125 Polymer membrane electrode, Ca2+ 020955856 (6.0508.110) Surfactants in aqueous media Tego® trant A 100,2 see AB 233 Ionic surfactant electrode 020959321 (6.0507.120) c(KCl) = 3 mol/L 020096101 (6.2308.020) a separate reference electrode is needed. Order Nr: 6.0726.100 sodium lauryl sulphate, see AB 233 Ionic surfactant electrode 020959321 (6.0507.120) c(KCl) = 3 mol/L 020096101 (6.2308.020) a separate reference electrode is needed. Order Nr: 6.0726.100 Sodium tetra phenyl borate, see AB 230, AB 263 NIO surfactant electrode 020959304 (6.0507.010) Inner chamber of the reference electrode: c(KCI) = 3 mol/L 020096101 (6.2308.020) Outer chamber: c(NaCL) = 1 mol/L a separate reference electrode is needed. Order Nr: 6.0726.107 Non aqueous surfactants Nonaqueous media, solvents as Chloroform, MIKB, see AB 269 Surfactrode resistant 020959312 (6.0507.130) c(KCl) = 3 mol/L 020096101 (6.2308.020) a separate reference electrode is needed. Order no: 20 94 411-1 (6.0726.107) electrode not suitable for high salt concentrations and pH > 10 Nonaqueous media, solvents as MIKB Two phase titration, see AB 269 Surfactrode refill 020959339 (6.0507.140) c(KCl) = 3 mol/L 020096101 (6.2308.020) a separate reference electrode is needed. Order no: 20 94 411-1 (6.0726.107) 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 (020094451) is an electrolyte solution for non-aqueous titrations. It is very useful when titrating low acid contents with TBAOH. In such cases the 2 mol/L LiCI in ethanol (020094435) 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 020959274 (6.2317.000) (6 g) 020959282 (6.2317.010) (60 g) Available on request 6.2317.020 (500 g) 3 To connect an electrode with plug-in head G to a Titrino or 726/796 Titroprocessor, use one of the following cables: 020977345 (1 m) or 020977353 (3 m). See Metrosensor Electrode Catalog for additional information. Storage of the Solvotrode when not in daily use: Store the Solvotrode in 2 mol/L LiCI in ethanol. Use a normal Electrode holder. Articles