Sodium sulfuric acid (thiosulfate) standard titers (fixed), Zaporizhia region.

Sodium sulphurous acid (thiosulfate) standard titers (fixed samples).
Standard titers Sodium sulphide
The solution prepared from standard titers of sodium sulfite is used for chemical analysis when determining the quality of raw materials, products and other substances by the method of oxidation-reduction (oxidimetry)(//tractor-service.com)
Fixanaly sodium sulfate guarantees obtaining a precisely known concentration of the solution, allowing to conduct the research with the required accuracy.
Standard-titre sodium sulfuric acid (thiosulfate) preparation of solution
To prepare a fixanal solution of sodium sulfite, pour the drug into a laboratory flask, add distilled water at a temperature of 20°C and mix thoroughly. Then the resulting solution is brought to a volume of 1000 cm3 with distilled water and mixed again. They get a solution with a concentration of (Na2S2O3·5H2O)=0.1mol/dm3 (0.1n)