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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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:
7 July 2000 - 12 July 2000
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Study conducted in compliance with agreed protocols, with no or minor deviations from the standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results. The study report was conclusive, done to valid guidelines and conducted under GLP conditions.
Qualifier:
according to guideline
Guideline:
EPA OPPTS 830.7950 (Vapor Pressure)
Deviations:
no
Qualifier:
according to guideline
Guideline:
OECD Guideline 104 (Vapour Pressure Curve)
Deviations:
no
GLP compliance:
yes
Type of method:
effusion method: by loss of weight or by trapping vaporisate
Key result
Test no.:
#1
Temp.:
25 °C
Vapour pressure:
0 Pa
Test no.:
#1
Temp.:
25 °C
Vapour pressure:
0 mm Hg
Key result
Test no.:
#1
Temp.:
20 °C
Vapour pressure:
0 Pa
Test no.:
#1
Temp.:
20 °C
Vapour pressure:
0 mm Hg

Results

Validation of the High and Low end Capacity:

The vapour pressures of several compounds of known vapour pressure were measured using multiple orifice sizes. Since the vapour pressure for all the orifices could be fitted linearly (with error limits of ± 30 % for the high end, and a factor of 3 for the low end), it was concluded that the present setup is capable of measuring vapour pressure between 0.8 mmHG (107 Pa) and 5 x 10E-10 mmHG (6.7 x 10E-08 Pa).

Vapour Pressure Determination:

A total of 0.5 % of the starting weight of the sample was lost before the first data point in Table 1 was calculated. The total weight loss during the experiment was 2.9 %.

The vapour pressure data have been fit to the Clausius-Clapeyron equation, by a least squared method, to yield the following:

To calculate pressure in mHg

Log10 Pressure (mmHg) ± 0.05 = 18.79-8960.9/(Temperature, K)

To calculate pressure in Pa

Log10 Pressure (Pa) ± 0.05 = 20.91-8960.9/(Temperature, K)

Figure 1 shows the plot of all vapour pressure data and the fitted curve.

Table 1: Results

Temp

(°C)

Rate of Wt Loss

(mg/hr)

Orifice Size

(cm)

Clausing Factor

Vapour Pressure

torr

Pa

90.11

6.31E-02

0.5200

0.882

1.35 E-06

1.80 E-04

92.11

7.54 E-02

0.5200

0.882

1.62 E-06

2.15 E-04

97.10

1.82 E-01

0.5200

0.882

3.94 E-06

5.25 E-04

99.09

2.42 E-01

0.5200

0.882

5.24 E-06

6.98 E-04

104.09

4.81 E-01

0.5200

0.882

1.05 E-05

1.40 E-03

105.08

5.55 E-01

0.5200

0.882

1.21 E-05

1.61 E-03

106.09

6.45 E-01

0.5200

0.882

1.41 E-05

1.88 E-03

 

 

 

 

 

 

71.14

8.43 E-03

0.9880

0.953

4.68 E-08

6.24 E-06

73.13

1.52 E-02

0.9880

0.953

8.50 E-08

1.13 E-05

78.13

3.18 E-02

0.9880

0.953

1.78 E-07

2.38 E-05

80.12

5.93 E-02

0.9880

0.953

3.34 E-07

4.45 E-05

85.12

1.18 E-01

0.9880

0.953

6.70 E-07

8.93 E-05

87.12

1.41 E-01

0.9880

0.953

8.02 E-07

1.07 E-04
Conclusions:
Under the conditions of the test, the vapour pressure was determined to be 7.19 E-10 Pa at 25 °C and 2.20 E-10 Pa at 20 °C.
Executive summary:

The vapour pressure of the test material was determined in a GLP study performed according to the standardised guidelines EPA OPPTS 830.7950 and OECD 104 using the Knudsen-effusion/weight loss method.

An amount of material effusing through the opening of the cell was measured continuously with a recording microbalance working in high vacuum. The rate of weight loss of the sample (contained in a cell) through an orifice of known area and kept at an isothermal temperature was recorded and converted to the vapour pressure of the sample by calculation.

Under the conditions of the test, the vapour pressure was determined to be 7.19 E-10 Pa at 25 °C and 2.20 E-10 Pa at 20 °C.

Description of key information

Vapour pressure 7.19 E-10 Pa at 25 °C and 2.20 E-10 Pa at 20 °C, effusion method, EPA OPPTS 830.7950, OECD 104, Griffin 2000.

Key value for chemical safety assessment

Vapour pressure:
0 Pa
at the temperature of:
25 °C

Additional information

The vapour pressure of the test material was determined in a GLP study performed according to the standardised guidelines EPA OPPTS 830.7950 and OECD 104 using the Knudsen-effusion/weight loss method. The study was assigned a reliability score of 1, reliable without restrictions, in line with the principles of Klimisch et al. (1997).

An amount of material effusing through the opening of the cell is measured continuously with a recording microbalance working in high vacuum. The rate of weight loss of the sample (contained in a cell) through an orifice of known area and kept at an isothermal temperature was recorded and converted to the vapour pressure of the sample by calculation.

Under the conditions of the test, the vapour pressure was determined to be 7.19 E-10 Pa at 25 °C and 2.20 E-10 Pa at 20 °C.