Disodium [6-[(2-anilino-1-naphthyl)azo]-2,4-dinitrophenolato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]naphthalene-1-sulphonato(3-)]chromate(2-)

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From July 19th to August 13th, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

adopted in 1995

GLP compliance:

yes

Type of method:

flask method

Water solubility:

88.5 g/L

Conc. based on:

test mat.

Incubation duration:

24 - 72 h

Temp.:

20 °C

pH:

8.5 - 8.6

Details on results:

MAIN TEST
The solution of each flask has been measured twice at 20 °C.
To verify the accuracy of the analytical method, freshly prepared standard solutions (prepared with the test item) were measured in between the samples of the flask method; the recovery rate of the measured standard solutions was in the range from 98.4 % to 100.8 %, which shows a good accuracy of the analytical method.

PRELIMINARY TEST
The preliminary test at room temperature showed that water solubility of test item was between 7.9 g/l and 29.8 g/l.

Flask	1a	2a	3a	4a
measured value [mg/l]	87.97 / 87.52	89.50 / 90.63	88.88 / 87.47	-- / --
pH value at 23 °C	8.5	8.5	8.6	7.1
average water solubility [g/l]*	87.25	90.06	88.18	--
mean value of the water solubility [g/l]	88.5			--
standard deviation [mg/l]	1.44			--
relative standard deviation [%]	1.62			--

*Considering the solution factor of 1000

Conclusions:

88.50 g/l at 20 °C and pH 8.5 to 8.6

Executive summary:

Water solubility of the substance was investigated according to the OECD guideline 105. The preliminary test, conducted at room temperature, showed that water solubility of test item was between 7.9 g/l and 29.8 g/l, thus flask method was used for the main experiment.

The concentration in the clear aqueous phase was determined by HPLC-UV validate method. The pH of each sample was recorded. The water solubility of test item was determined to be 88.50 g/l at 20 °C and pH 8.5 to 8.6

To verify the accuracy of the analytical method, freshly prepared standard solutions (prepared with the test item) were measured in between the samples of the flask method; the recovery rate of the measured standard solutions was in the range from 98.4 % to 100.8 %, which shows a good accuracy of the analytical method.

Conclusion

Water solubility: 88.50 g/l at 20 °C and pH 8.5 to 8.6

Description of key information

88.50 g/l at 20 °C and pH 8.5 to 8.6

Key value for chemical safety assessment

Water solubility:

88.5 g/L

at the temperature of:

20 °C

Additional information

OECD 105 - flask method