Karl Fischer & Potentiometric Titration Application Library

Determination of sodium chloride in sodium hypochlorite | Autotitrator COM-A19
Sodium hypochlorite is produced by having sodium hydroxide absorb chlorine gas. Produced sodium hypochlorite contains residual alkali (sodium hydroxide, sodium carbonate) and sodium chloride generated by the degradation of hypochlorous acid. The residual alkali is determined by neutralization titration, and sodium chloride is determined by precipitation titration.
This report introduces an example of the determination for sodium chloride in the sodium hypochlorite with potentiometric titration.

Determination of residual alkali in sodium hypochlorite | Autotitrator COM-A19
Sodium hypochlorite is produced by having sodium hydroxide absorb chlorine gas. Produced sodium hypochlorite contains sodium chloride generated by the degradation of hypochlorous acid.
This report introduces an example for the determination of residual alkali (sodium hydroxide, sodium carbonate) in the sodium hypochlorite with potentiometric titration.

Determination of available chlorine in sodium hypochlorite | Autotitrator COM-A19
This report introduces an example for determination of available chlorine as follows:.
1) Add potassium iodide to sodium hypochlorite to generate free iodine.
2) Titrate the free iodine generated from the reaction (1) with sodium thiosulfate to determine available chlorine (2) by redox titration.
Cl₂ +2KI → I₂ + 2KCl・・・(1)
I₂ + 2Na₂S₂O₃ → 2NaI + Na₂S₄O₆・・・(2)

Fractional determination for mixture of sodium hydroxide and sodium carbonate | Autotitrator COM-A19
Sodium hydroxide and sodium carbonate have important roles as alkali component chemicals, which are used in a broad range of industries. The concentration of both components have to be determined because these are sometimes used with mixed.
This report introduces an example that the mixture solution of sodium hydroxide and sodium carbonate are fractionally determined with potentiometric titration.

Purity determination of sodium hydroxide | Autotitrator COM-A19
Sodium hydroxide is one of the most elemental reagent in chemical industrial reagents. Its production amount is large and it is used in a broad range of fields. Sodium hydroxide absorbs carbonate gas and water in atmosphere because of its properties, the purity of sodium hydroxide is gradually reduced. Japanese Industrial Standard (JIS) K8576 defines determination method for purity of sodium hydroxide (titration with indicator). Representative impure substance in sodium hydroxide includes sodium carbonate.
This report introduces an example for the quantitative determination of sodium hydroxide purity and sodium carbonate by successive and fractional potentiometric titration.

Copper (Cu²⁺) Analysis in Copper Sulfate Plating Baths Using EDTA Titration
Accurately measure copper (Cu²⁺) concentration in copper sulfate plating baths using automated potentiometric EDTA titration. Learn how the COM-A19 auto titrator improves plating bath control, repeatability, and production quality while reducing operator error.

Quantitative determination of lead ion | Autotitrator COM-A19
The chelatometric titration is generally used for the determination of lead ion (Pb2+). The pH region the lead ion can be directly titrated is pH 3.5 ~ 10 (stability constant = 17.88).1 However, it generates Pb(OH)2 precipitation at alkaline region. When performing titration under alkaline condition, the auxiliary complexing agent such as ethanolamine, tartaric acid, or citric acid should be added in advance to generate weak chelatometric complex and avoid the generation of lead hydroxide precipitation.
It is titrated at pH around 4 ~ 5 when performing under acidic condition. This report introduces an example that the lead ion in sample solution adjusted to pH 5 by hexamine solution is determined with using XO indicator (red purple →yellow).
Pb²+ + Na₂EDTA → Pb-EDTA + 2Na+

Quantitative determination of manganese ion | Autotitrator COM-A19
Mn²+ + Na₂EDTA → Mn-EDTA + 2Na+

Determination of ferrous and ferric ion in steel cleaning solution | Autotitrator COM-A19
Fe³+ + Na₂EDTA → FeEDTA + 2Na+
Fe²+ → Fe³+ + e-

Determination of trace chloride ion in copper sulfate solution | Autotitrator COM-A19
This report introduces an example of the determination of trace chloride ion in the solution containing highly concentrated copper sulfate.
The precipitation titration with silver nitrate standard solution is generally used for the determination of chloride ion in copper sulfate solution. The endpoint of the titration is detected with indicator method or the potentiometric method. The potentiometric method is used for this sample because the color change of indicator reagent is obscure in this sample containing highly concentrated copper sulfate. However, it tends to show the difficulty to detect the endpoint because of the less sensitivity of electrode under highly concentrated copper sulfate. Therefore the potentiometric titration is performed with the specially treated silver electrode that the silver chloride is coated.
Cl- + AgNO₃ → AgCl + NO₃-

Quantitative determination of zinc ion | Autotitrator COM-A19
Zn²⁺ + Na₂EDTA → Zn-EDTA + 2Na⁺

Copper Analysis in Copper Sulfate Plating Baths Using Redox Titration
Copper concentration is critical to plating performance and coating quality. Learn how automated redox titration improves accuracy, repeatability, and process control in copper sulfate baths.



