Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Additional information

Appearance/physical state/colour

On the basis of physical observation and using the sense of smell, the substance calcium iodate was found to be an odourless white coloured amorphous inorganic solid at 20°C and 1013 hPa.

 

Melting point/freezing point

The melting point of calcium iodate by the capillary method was found to be 535°C at an atmospheric pressure of 975 hPa. Melting point value at 101325 Pa is equivalent to 555.98°C. There was no decomposition & sublimation observed for calcium iodate at the melting point.

 

Boiling point

The boiling point of the substance need not be conducted as the substance has melting point above 300°C and decomposes before boiling and so as per the section 7.3 of Annex VII this end point can be waived.

 

Density

The bulk density of calcium iodate by the mass by volume method was found to be 4.79 g/cm³ at room temperature of 25°C.

This value at 20°C is equivalent to 5.9875 g/cm³.

 

Particle size distribution (Granulometry)

Based on the principle of measurement of relative amounts of particles present, sorted according to size, sieve analysis method have been used in this case and the particle size distribution (granulometry) of calcium iodate by the sieve analysis method was found to be in the range of 53 micrometer to 500 micrometer. Majority of the particles were found to be in the size ranges 53-75(25.34 %) and 75-150 (37.67%) micrometer in size.

 

Vapour pressure

The vapour pressure of calcium iodate was estimated as 0.000000000000196 Pa at 25°C by Modified Grain Method.

 

Partition coefficient

The estimated value of the octanol-water partition co-efficient (log Pow) of calcium iodate is -5.28 at 25°C. This value indicates that calcium iodate is hydrophilic in nature.

 

Water solubility

The experimental value of the water solubility of calcium iodate was found to be 210000 mg/L at 25°C. This value indicates that the substance is very soluble in water.

The supporting studies show values different from the key study which could be due to the difference in the estimation conditions. However for the purpose of the chemical safety assessment, the key study values shall be used.

 

Solubility in organic solvents / fat solubility

Gravimetric method was used to determine the solubility of the substance in organic solvent. The solubility of calcium iodate in alcohol is observed to be nil at 25°C. In other words the substance was found to be insoluble in alcohol.

Using the Soxhlet/Solvent extraction method the solubility of the substance in petroleum ether is observed to be 3900 mg/L at 25 °C indicating that the substance is soluble in petroleum ether. The solubility value of Calcium iodate in petroleum ether at 20°C is equivalent to a value of 3120 mg/L.

 

Surface tension

In accordance with Column 2 adaptation statement of REACH Annex VII, information requirement 7.6, this end point was considered for waiver since surface activity was not a desired property of Calcium iodate.

 

Flash point

In accordance with column 2 of Annex VII, flash point does not need to be conducted if the chemical is inorganic. Since calcium iodate is an inorganic chemical, this end point was considered to be waived.

 

Auto flammability

The substance Calcium iodate is non flammable in nature and does not have the property of self ignition.

 

Flammability

Calcium iodate ignites only when the flame of Bunsen burner having temperature of 950°C is brought in contact with it. Thus it can be concluded that calcium iodate is flammable only at high temperature of about 950°C. However since such high temperatures are not found under normal circumstances of transportation and use, calcium iodate was considered non-flammable for chemical safety assessment.

 

Explosiveness

According to theoretical considerations based on chemical structure, Calcium iodate does not possess explosive properties. The reason for this is there are no chemical groups associated with explosive properties in Calcium iodate. Thus, as per column 2 of Annex VII this end point was considered for waiver.

 

Oxidising properties

Calcium iodate was found to have oxidising property since 18.9 ml of KMnO4 was required for getting the end point of the redox titration for 100 g of Calcium iodate. Thus, calcium iodate is considered to be an oxidising solid as per the result obtained and the classification of the substance will be in category 2.

 

Stability in organic solvents and identity of relevant degradation products

In accordance with column 2 of Annex 9, this study does not need to be conducted if the substance is inorganic and calcium iodate is an inorganic substance. Hence this study was considered for waiver.

 

pH

1 % by volume solution of Calcium iodate was found to exhibit a pH of 9.15 at 26°C. Thus 1% by volume solution of Calcium iodate is basic in nature.

 

Dissociation constant

The experimental pKa value for Calcium iodate was found to be 0.00000655 at 25°C indicating that it has dissociation properties. This pKa value at 20°C is equivalent to a value of 0.00000524.

 

Viscosity

This end point was considered for waiver since viscosity is an inherent property of a liquid that offers resistance to its flow and Calcium iodate is a solid substance and hence this testing was considered scientifically unjustified for Calcium iodate.