Diammonium tartrate

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-11-24 to 2015-11-25

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

GLP compliance:

no

Type of method:

effusion method: Knudsen cell

Specific details on test material used for the study:

Storage conditions: Ambient temperature (10 to 30 °C)

Temp.:

31 °C

Vapour pressure:

0.001 Pa

Remarks on result:

other: experimental value, not a fitted value

Temp.:

40 °C

Vapour pressure:

0.002 Pa

Remarks on result:

other: experimental value, not a fitted value

Temp.:

20 °C

Vapour pressure:

0.001 Pa

Remarks on result:

other: conservative approach: Value from experimental data of 31°C used

Temp.:

25 °C

Vapour pressure:

0.001 Pa

Remarks on result:

other: Conservative approach:Value from experimental data of 31°C used

Experimental data for T=31, 40, 50, 60, 70, 80, 91, 100, 110 °C are given in table above

Temperature °C	Vapor pressure/ Pa
31	1.1x10-3
40	1.7x10-3
50	8.7x10-4
60	9.8x10-4
70	1.2x10-3
80	1.6x10-3
91	3.5x10-3
100	5.8x10-3
110	7.5x10-3

Substance shows unusual behaviour behaviour for vapor pressure over the complete temperature range. Due to this unusual behaviour no extrapolation by Antoine equation was done. Therefore no vapor pressure values at 20°C and 25°C were determined by extrapolation from higher temperatures. For 20° and 25°C a conservative approach was applied taking temperature for 31°C.

Description of key information

1.7E-03 Pa at 40 °C

1.1E-03 Pa at 31 °C

1.1E-03 Pa at 20 °C (conservative approach, taken from 31 °C)

Key value for chemical safety assessment

Vapour pressure:

0.001 Pa

at the temperature of:

20 °C

Additional information

Vapor pressure was measured by cell diffusion method. The non GLP study was conducted according to the OECD guideline 104 and EU Method A.4. Vapor pressure values were measured between the temperature range of 31 °C and 110 °C in steps of 10 °C. The substance showed unusual behavior of vapor pressure over the complete temperature range. There is no linear dependency of log (vapor pressure) vs 1/T. Complete outliers are vapor pressure values of 31 °C and 40 °C which have vapor pressure values one magnitude higher than expected. Therefore no fitting and extrapolation by the Antoine equation could be performed. Reported vapor pressure values for 31 °C and 40 °C were taken directly from experimental data which are higher than the fitted values. For temperature values of 20 °C and 25 °C experimental data from the 31 °C were taken as a conservative approach. Reason for the unusual behavior could be impurities, water, and decomposition products.