Benzamide, N-[[4-[(cyclopropylamino)carbonyl]phenyl]sulfonyl]-2-methoxy-

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Hess. Ministerium für Umwelt, Landwirtschaft und Forsten, Wiesbaden, Germany

Type of method:

effusion method: vapour pressure balance

Temp.:

20 °C

Vapour pressure:

< 0 Pa

Remarks on result:

other: estimated value according to the Antoine equation

Vapour pressure:

< 0 hPa

Remarks on result:

other: The vapour pressure values were calculated as conservative estimates, based on a lack of any detectable vapour pressure of the test item at 150.1 °C, and the detection limit of the method, i.e. 10e-5 hPa.

The vapour pressure was measured in the temperature range of 50 to 150 °C.

No vapour pressure of the test item was observed in the entire range, meaning that the vapour pressure in the whole range was below the lower detection limit of 10^-5hPa. The vapour pressure was measured at the following temperatures: 50.1, 58.1, 63.5, 70.7, 77.6, 84.4, 91.5, 99.8, 100.1, 111.3,119.5, 128.6, 133.6, 140.0 and 150.1 °C. For every temperature the vapour pressure of the test item was <10^-5hPa.

 

Estimation of the vapour pressure for the test item at 20, 25 and 50 °C

According to the Antoine equation, the vapour pressure can be calculated according to:

Log p = A + B/(273.15 +T)

[p in hPa and T in °C]

Values for the slope of the Antoine equation (constant B) for comparable substances, which can be found in the literature (e.g. Handbook of Chemistry and Physics) are normally lower than - 5000.

Thus, for a conservative estimation of the vapour pressure of the test item at 20, 25 and 50 °C, a slope (constant B) of - 5000 was used.

The last data point of the measurement at 150.1 °C was used as the starting point for the calculation.

The measured vapour pressure at 150.1 °C was below 10^-5hPa. For a conservative estimation, it was assumed that the vapour pressure at 150.1 °C corresponds to the lower detection limit of the vapour pressure balance, i.e. 10^-5hPa.

Based on this assumption, the constant A of the Antoine equation was calculated according to

A = log p - [B / (273.15 + T)] = log10^-5- [- 5000 / (273.15 + 150.1)] = 6.8133

 

Subsequently, the vapour pressure at 20, 25 and 50 °C can be calculated with the Antoine equation as follows:

Log p = 6.81 - 5000 / (273.15 +T)                                      p in hPa and T in °C

 

T [°C]	p [hPa]	p [Pa]
20	5.72E-11	5.72E-9
25	1.10E-10	1.10E-8
50	2.19E-9	2.19E-7

 

This is a conservative estimation of the vapour pressure of the test item for the listed temperatures.

Since the true vapour pressure is most likely to be even much lower than this value derived from the detection limit, it may safely be assumed that the vapour pressure at the above listed temperatures is far below 10 ^-7hPa

 

T [°C]	p [hPa]	p [Pa]
20	<< 1.0E-7	<< 1.0E-5
25	<< 1.0E-7	<< 1.0E-5
50	<< 1.0E-7	<< 1.0E-5

 

Description of key information

< 0.00001 Pa at 20 °C

(OECD 104, effusion method: vapour pressure balance)

Key value for chemical safety assessment

Vapour pressure:

0 Pa

at the temperature of:

20 °C