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 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is an odourless light brown coloured organic solid.

Melting point/freezing point :

The melting point of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid by the capillary method was found to be 380 degC at an atmospheric pressure of 960 hPa.There was no decomposition & sublimation observed of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid at the melting point.The other authoritative supporting sources of information also indicate the melting point of 3-acetamido-5-amino-4 hydroxybenzene sulphonic acid to be in the range 220 degC to 350 degC. However, for the purpose of the chemical safety report the experimental value of melting point will be considered.Melting point value at 101325 Pa works out to be 401.07 degC.

Boiling point :

The boiling point of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid by the distillation method was found to be 390 degC at the atmospheric pressure of 960 hPa.No decomposition of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid was observed at the boiling point.The other authoritative source of information though indicate the boiling point to be 517.53 degC.However for the purpose of the chemical safety report, the boiling point of the key study which is 390 deg c shall be considered.Boiling point value at 101325 Pa works out to be 411.6 degC.

Density :

Experimental value of density of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid by the mass by volume method was found to be 0.74 g/cm3 at room temperature of 30 °C. The relative density value when converted for 20 °C is equivalent to 0.493 g/cm3.The supporting studies show values different from key study which could be due to difference in the estimation conditions.However for the purpose of chemical safety assesement the study value shall be considered.

Particle size distribution (Granulometry) :

The particle size distribution (granulometry) of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid by the sieve method was found to range from 150 micro meter to 710 micrometer. However majority of the particles(77%)were 500 micrometer in size.

Vapour pressure :

According to DEPA QSAR and EPI Suite, vapour pressure of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is estimated as 0.0000000000004 mmHg by modified Grain method.This value when convereted into pascal is equivalent to 0.000000005333Pascal(Pa).This indicates a very low value of vapour pressure.

Partition coefficient :

The experimental value of octanol water partition co-efficient (Log Pow) of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is -0.301 at 30deg C and pH of 3.05. This value indicates that the substance is hydrophobic in nature.Data from various modelling databases also show that this substance is hydrophobic in nature.

Water solubility :

The experimental value of the water solubility of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid was found to be 2000 mg/L at 30 deg C indicating that it is soluble in water.

Solubility in organic solvents / fat solubility :

The experimental value of solubility of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid in methanol at 30 deg C was found to be 1000 mg/L This value at 20 degC is equivalent to 666.66666666666667 mg/L.Thus,it can be concluded that this substance exhibits greater solubility in water than organic solvents like methanol and petroleum ether.

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 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid.

Flash point :

The experimental value of flash point of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid by the closed cup method was found to be 385°C at 960 hPa. This value when converted into 101 325 pascal is equivalent to 406.35 °C.

Auto flammability :

3-acetamido-5-amino-4-hydroxybenzenesulphonic acid did not catch fire on being exposed to air at room temperature of 30°C and atmospheric pressure of 960 hPa. This indicates that 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is not auto-flammable.

Flammability :

3-acetamido-5-amino-4-hydroxybenzenesulphonic acid did not catch fire on being exposed to air at room temperature of 30 degC and atmospheric pressure of 975 hPa. This indicates that 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is not auto-flammable

Explosiveness :

In accordance with column 2 of Annex VII, this end point was considered for wiaver since there are no chemical groups associated with explosive properties in 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid and therefore 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is unlikely to be explosive.Information requirement 7.11, this testing was not conducted since there are no chemical groups in , associated with explosive properties. Hence, this endpoint is considered as waived for the purpose of this registration dossier.

Oxidising properties :

3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is found to be oxidising with the redox titration yielding an end point of 141.3 ml KMnO4 per 100g of analyte 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid.

Stability in organic solvents and identity of relevant degradation products :

3-acetamido-5-amino-4-hydroxybenzenesulphonic 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 :

pH value of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is found to be 4.59 at temp. 25 °C and 1% concentration.

Dissociation constant :

The experimental Dissociation constant (pKa) values of 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid at 30 °C are found to be as follows:

0.000000165, 0.000000166 and 0.000000175 indicating that it has dissociation properties.The average pKa value at 20 Deg C is equivalent to 0.00000011244444466667

Viscosity :

This end point was considered for waiver since viscosity is an internal property of a liquid that offers resistance to flow and 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid is a solid substance and hence this testing was considered scientifically unjustified for 3-acetamido-5-amino-4-hydroxybenzenesulphonic acid.