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,Eicosanoic acid is a light yellow colour granular organic solid substance with no odour at 33 degC and 990 hPa.

Melting point

The melting point of Eicosanoic acid by the capillary method was found to be 46.7 degC at an atmospheric pressure of 990 hPa.There was no decomposition & sublimation observed of Eicosanoic acid at the melting point.This melting point value when converted at 101325 Pa is equivalent to a value of 47.796 degC.

Boiling point

The Boiling Point of Eicosanoic acid by the distillation method was found to be 325 degC at the atmospheric pressure of 990 hPa .No decomposition of Eicosanoic acid was observed at the boiling point.This boiling point value when converted at 101325 hPa is equivalent to 332.63 degC.

Density

The bulk density of Eicosanoic acid by the mass by volume method was found to be 0.535 g/cm3 at room temperature of 33 degC.This value when converted at 20 degC is equivalent to 0.324.

Particle size distribution (Granulometry)

The particle size distribution (granulometry) of Eicosanoic acid by the sieve analysis method was found to be in the range of 600 micrometer to 1000 micrometer. Majority of the particles were found to be in the size more than 1000 (65.03%) micrometer in size.

Vapour pressure

The vapour pressure of Eicosanoic acid was estimated to be 0.000044663 Pa at 25°C by means of Modified and Grain Method.

Partition coefficient

The experimental value of octanol water partition co-efficient (log Pow) of Eicosanoic acid is 1.571 at 33 degC and pH of 3.52.This value indicates that Eicosanoic acid is hydrophilic in nature.

Water solubility

The experimental value of the water solubility of Eicosanoic acid was found to be 44 mg/L at 33 degC indicating that the chemical is slightly soluble in water.

Solubility in organic solvents / fat solubility

Gravimetric method was used to determine the solubility of the substance in organic solvent.The experimental value of solubility of Eicosanoic acid in methanol at 33 degC was found to be 1100 mg/L indicating that the substance is soluble in methanol.Using the Soxhlet/Solvent extraction method the solubility of the substance in Petroleum ether is observed to be 2700 mg/L at 33 deg C,indicating that the substance is soluble in Petroleum ether. The solubility value of Eicosanoic acid in Petroleum ether at 20 degC is equivalent to a value of 1636.36 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 for the substance, Eicosanoic acid as it is solid in character.

Flash point

The experimental value of flash point of Eicosanoic acid by the open cup method was found to be 134 degC at 990 hPa atmospheric pressure.This flash point value when converted at 101325 Pa is equivalent to 137.14 degC.

Auto flammability

Eicosanoic acid did not catch fire on being exposed to air at room temperature of 33 degC and atmospheric pressure of 990 hPa. This indicates that Eicosanoic acid is not auto-flammable.

Flammability

From the experimental value of flammability, Eicosanoic acid ignited when the flame of bunsen burner having temperature of 950 degC was brought in contact with it. Thus it can be concluded that Eicosanoic acid is flammable only at high temperature of about 950 deg C. However since such high temperatures are not found under normal circumstances of transportation and use, Eicosanoic acid was considered non-flammable for chemical safety assessment.

Explosiveness

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

Oxidising properties

Eicosanoic acid was found to have mild oxidising property since 98.75 ml of KMnO4 was required for getting the end point of the redox titration for 100 g of Eicosanoic acid.Thus, the chemical is considered as non-oxidising for the purpose of chemical safety report and classification.

Stability in organic solvents and identity of relevant degradation products

Eicosanoic acid was found to be stable in organic solvent dichloro methane and no degradation products were formed after 24 hours as evident from the GC-MS chromatogram obtained at 0 hours and that obtained after 24 hours.

pH

1% by volume solution of Eicosanoic acid was found to exhibit a pH of 4.85 at 25 degC. Thus 1% by volume solution of Eicosanoic acid is acidic in nature.

Dissociation constant

The experimental pKa value for Eicosanoic acid was found to be 0.00000006 at 33 deg C indicating that the chemical has dissociation properties.This pka value when converted at 20 degC is equivalent to 0.000000036.

Viscosity

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