5-nitrosalicylic acid

Endpoint summary

Additional information

Appearance/physical state/colour

On the basis of physical observation and using the sense of smell, 5-nitrosalicylic acid was found to be a Colorless organic amorphous solid with no odor at 25°C and 995 hPa.

Melting point/freezing point

From experimental study details melting point of the 5-nitrosalicylic acid is found to be 220°C at pressure 995 hpa by capillary method. At 101 325 Pa melting point of test substance was equivalent to 224.035°C.There was no decomposition & sublimation observed for 5-nitrosalicylic acid at the melting point.supporting study also indicate that the melting point of test substance is in the range of 225 -235 deg.C.

 

Boiling point

The boiling point of a substance is the (thermal) point at which a liquid substance gains enough thermal energy to become a gas.The boiling point of 5-nitrosalicylic acid by distillation method is observed to be 230 °C at vapour pressure 995 hpa. This boiling point at 101 325 hPa is equivalent to 234.218 °C.

Density

The bulk density of 5-nitrosalicylic acid by the mass by volume method was found to be 0.729 g/cm3 at room temperature of 25°C.This value when converted at 20 degC is equivalent to 0.5832 g/cm3.

Particle size distribution (Granulometry)

The particle size distribution (granulometry) of 5-nitrosalicylic acid 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 more than 500 (21.25%) - 53 (39.12%) micrometer in size.

Vapour pressure

From PBT profiler interpretation the vapour pressure of 5-nitrosalicylic acid was estimated to be 0.0000173 Pa at 25°C.

Partition coefficient

The experimental value of octanol water partition co-efficient (log Pow) of 5-nitrosalicylic acid is 1.1576 at temperature 25 degC and pH of 3.18. This value indicates that 5-nitrosalicylic acid is hydrophobic in nature.

Water solubility

The experimental value of the water solubility of 5-nitrosalicylic acid was found to be 88 mg/L at 25 degC indicating that it 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 5-nitrosalicylic acid in methanol at 25 degC was found to be 4150 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 52 mg/L at 25 °C, indicating that the substance is slightly soluble in petroleum ether. The solubility value of 5-nitrosalicylic acid in methanol at 20 degC is equivalent to a value of 3320 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 5-nitrosalicylic acid.

Flash point

The experimental value of flash point of 5-nitrosalicylic acid by the open cup method was found to be 121degC at 995 hPa.This flash point value when converted at 101325 is equivalent to 123.219°C

Auto flammability

5-nitrosalicylic acid did not catch fire on being exposed to air at room temperature of 25 degC and atmospheric pressure of 995 hPa. This indicates that 5-nitrosalicylic acid is not auto-flammable.

Flammability

From the experimental values of flammability, 5-nitrosalicylic 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 5-nitrosalicylic acid is flammable only at high temperature of about 950 degC. However since such high temperatures are not found under normal circumstances of transportation and use, 5-nitrosalicylic acid was considered non-flammable for chemical safety assessment. 

Explosiveness

According to theoretical considerations based on chemical structure, 5-nitrosalicylic acid does not possess explosive properties. The reason for this is there are no chemical groups associated with explosive properties in 5-nitrosalicylic acid Thus, as per column 2 of Annex VII this end point was considered for waiver.

Oxidising properties

5-nitrosalicylic acid was found to have mild oxidising property since 125.28 ml of KMnO4 was required for getting the end point of the redox titration for 100 ml of 5-nitrosalicylic 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

5-nitrosalicylic 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 5-nitrosalicylic acid was found to exhibit a pH of 1.88 at 23 degC. Thus 1% by volume solution of 5-nitrosalicylic acid is acidic in nature.

Dissociation constant

The experimental pKa value for 5-nitrosalicylic acid was found to be 0.00317 to 0.00318 at 25 degC indicating that it has dissociation properties.This pka value when converted at 20 degC is equivalent to 0.002544

Viscosity

This end point was considered for waiver since viscosity is an inherent property of a liquid that offers resistance to its flow and 5-nitrosalicylic acid is a solid substance and hence this testing was considered scientifically unjustified for 5-nitrosalicylic acid.