7-acetamido-4-hydroxy-3-[[4-[[2-(sulphooxy)ethyl]sulphonyl]phenyl]azo]naphthalene-2-sulphonic acid, sodium salt

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

04. September 2013-18. September 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Deviations:

no

GLP compliance:

yes

Type of method:

ring method

Key result

Surface tension:

67.21 - 67.32 mN/m

Temp.:

20 °C

Conc.:

1 000.5 mg/L

Conclusions:

The surface tension of the aqueous solution at 20 °C is higher than 60 mN/m. The test item has no surface-active properties.

Executive summary:

An aqueous solution of the test item in de-ionized water with a concentration of 1000.5 mg/l was prepared, shaken and the clear orange solution was adapted to the measurement temperature for 30 minutes. After adapting to 20 °C the measurement of thesurface tension with the test itemwas carried out at 20 ±0.5°C (19.9 °C), as follows:

The solution to be measured is transferred to the measurement vessel, taking care to avoid foaming. The measurement vessel was placed on the table of the test apparatus. The measurement vessel was raised until the ring was immersed below the surface of the solution. The time from starting the measurement was recorded. Subsequently, the table top was lowered gradually and evenly at a rate of 0.3 cm/min to detach the ring from the surface until the maximum force was reached. The force was read on the tensiometer. The measurements were repeated until a constant surface tension value in 6 measurements is reached.

Table 1:

 

Measurement	1	2	3	4	5	6
Time (s)	833	894	956	1017	1078	1139
s(mN/m) uncorrected	72.84	72.78	72.77	72.74	72.72	72.73
s(mN/m) corrected by Zuidema and Waters	67.32	67.27	67.25	67.22	67.21	67.21

Due to the fact that the surface tension showed a slight time-dependence no mean value could be reported. However, the surface tension is higher than 60 mN/m. The test item has no surface-active properties.

Description of key information

The surface tension of the aqueous solution at 2°C is higher than 60 mN/m. The test item has no surface-active properties.

Key value for chemical safety assessment

Surface tension:

67.25

in mN/m at 20°C and concentration in mg/L:

1 000

Additional information

An aqueous solution of the test item in de-ionized water with a concentration of 1000.5 mg/l was prepared, shaken and the clear orange solution was adapted to the measurement temperature for 30 minutes. After adapting to 20°C the measurement of the surface tension with the test item was carried out at 20 ±0.5°C (19.9°C).

Due to the fact that the surface tension showed a slight time-dependence no mean value could be reported. However, the surface tension is higher than 60 mN/m. The test item has no surface-active properties.