Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Physical & Chemical properties

Vapour pressure

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
key study
Study period:
from 2020-02-26 to 2020-02-28
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 104 (Vapour Pressure Curve)
Version / remarks:
2006
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method A.4 (Vapour Pressure)
Version / remarks:
2008
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Type of method:
dynamic method
Key result
Test no.:
#1
Temp.:
20 °C
Vapour pressure:
0.025 Pa
Key result
Test no.:
#2
Temp.:
25 °C
Vapour pressure:
0.036 Pa

The vapour pressure was measured in the temperature range of 27 to 58 °C.

No.

Temperature / °C

Vapour pressure / Pa

1

27

4.71 ×10-2

2

33

6.56 ×10-2

3

37

7.47 ×10-2

4

42

1.07 ×10-1

5

47

1.68 ×10-1

6

52

2.36 ×10-1

7

58

3.41 ×10-1

The logarithm of the vapour pressure was plotted as a function if the inverse temperature 1/T. From the measured data points of the vapour pressure curve the constants A and B of the Antoine equation (log p = A + B/T) can be derived by regression of the data points to A = 8.1146 and B = -2848.56. Tha vapour pressure of the test item at 20, 25 and 50 °C was calculated by extra- and interpolation.

Temperature / °C

Vapour pressure / Pa

20

2.5 ×10-2

25

3.6 ×10-2

50

2.0 ×10-1

Conclusions:
The estimated vapour pressure of the test item at 20 °C is 2.5e-2 Pa.
Executive summary:

The vapour pressure of test item has been determined according to the effusion method described in OECD Guideline n. 104 (2006) and EU Regulation No 440/2008, Method A.4. Therefore, the test item is set under vacuum to ensure it is dry and degased before the actual test starts. The sample of the test item is then heated in a small furnace, placed in an evacuated bell jar. The furnace is covered by a lid with small holes of known diameters. The vapour of the substance, escaping through one of the holes, is directed onto a balance pan of a highly sensitive balance which is also enclosed in the evacuated bell jar. The time dependent increase of weight on the balance is defined as the evaporation rate. The vapour pressure can be derived from the evaporation rate using the Hertz-Knudsen equation.The vapour pressure of the test item was determined at seven different temperatures. The logarithm of the vapour pressure was plotted as a function if the inverse temperature 1/T. The vapour pressure at 20, 25 and 50 °C was calculated from the linear regression to be 2.5e-2, 3.6e-2 and 2.0e-1 Pa, respectively.

Description of key information

The estimated vapour pressure of the test item at 20 °C is 2.5e-2 Pa.

Key value for chemical safety assessment

Vapour pressure:
0.025 Pa
at the temperature of:
20 °C

Additional information

The vapour pressure of test item has been determined according to the effusion method described in OECD Guideline n. 104 (2006) and EU Regulation No 440/2008, Method A.4. Therefore, the test item is set under vacuum to ensure it is dry and degased before the actual test starts. The sample of the test item is then heated in a small furnace, placed in an evacuated bell jar. The furnace is covered by a lid with small holes of known diameters. The vapour of the substance, escaping through one of the holes, is directed onto a balance pan of a highly sensitive balance which is also enclosed in the evacuated bell jar. The time dependent increase of weight on the balance is defined as the evaporation rate. The vapour pressure can be derived from the evaporation rate using the Hertz-Knudsen equation.The vapour pressure of the test item was determined at seven different temperatures. The logarithm of the vapour pressure was plotted as a function if the inverse temperature 1/T. The vapour pressure at 20, 25 and 50 °C was calculated from the linear regression to be 2.5e-2, 3.6e-2 and 2.0e-1 Pa, respectively.