Potassium trifluorozincate

Endpoint summary

Additional information

Potassium trifluorozincate is a white powder that will melt under decomposition at temperatures >850 °C (Solvay SA, 2013). Its density is 3949 kg/m3 (Solvay SA, 2011) and its water solubility is 8.2 g/L at pH6 at room temperature (Solvay, 2011).

Determination of the boiling point and vapour pressure of KZnF3 does not need to be conducted as the melting point is well above 300 °C. Testing on partition coefficient, flash point and stability in organic solvent do not need to be performed as the substance is inorganic. Surface tension does not need to be determined as it is not expected based on the substance structure nor a desired substance property. The explosiveness does not need to be tested as KZnF3 does not contain chemical groups associated with explosive properties. The oxidising properties do not need to be tested as the substance is expected to be incapable of reacting exothermically with combustible materials based on its chemical structure. Testing of the following endpoints is considered scientifically unjustified according to section 1 of REACH Annex XI. Flammability and autoflammability were not tested as both metal ions (potassium and zinc) are already present in the highest possible oxidation state and fluorine is a more electronegative element than oxygen. The interaction with oxygen is therefore not possible and the substance is essentially non-flammable. Furthermore, based on the experience in handling the substance, the substance does not exhibit water reactivity or pyrophoric properties. The dissociation constant was not tested as KZnF3 is an inorganic salt which is expected to dissociate fully into the respective cation and anion in aqueous solution. The viscosity was not tested as KZnF3 is a solid and this property is relevant only for liquids. Particle size distribution finally, was determined by laser diffraction; results were as follows: D10 = 0.97 µm; D50 = 3.24 µm; D90 = 7.94 µm (Solvay SA, 2011).