N'-(1,3-dimethylbutylidene)-3-hydroxy-2-naphthohydrazide

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27-29 November 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Version / remarks:

Directive 92/69/EEC, A.4 (static technique) (EEC publ no. L383, Dec 1992)

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Version / remarks:

(1995)

GLP compliance:

yes

Type of method:

static method

Test no.:

#1

Temp.:

37.55 °C

Vapour pressure:

2.77 Pa

Remarks on result:

other: First vapour pressure

Test no.:

#2

Temp.:

31.18 °C

Vapour pressure:

1.33 Pa

Remarks on result:

other: Second vapour pressure

Test no.:

#3

Temp.:

24.21 °C

Vapour pressure:

0.56 Pa

Remarks on result:

other: third vapour pressure

Key result

Temp.:

20 °C

Vapour pressure:

0.33 Pa

Remarks on result:

other: Estimated vapour pressure value at 20°C using the least squares method.

At the beginning of the test, the vapour pressure of the test substance decreased slightly every next measurement, due to the removal of volatile impurities. After measurement 17 this decrease became negligible and the vapour pressure was stable. So from that moment on, the collected data were used for the final result.

Measurement	Temperature [°C]	mean vapour pressure [Pa]
18 -27	37.55	2.77 +/- 0.15
30 -37	31.18	1.33 +/- 0.03
40 -52	24.21	0.56 +/- 0.01

The experimenatlly determined vapour pressure values were plotted against the reciprocal temperature [T-¹] (in Kelvin; see attached background information), taking into account the calculated error.

Fitting these data using a least squares method gives a value of 0.326 Pa with 0.017 Pa for 2s_n-1(i.e. 2.5%) for the vapour pressure of the test substance at 20°C. The maximum deviation between the fit and the data points is always less than about 2%. Errors made in estimating the mean value per temperature series are up to 5.2%. So a value of 0.02 Pa (i.e. 6.1%) is a reasonable value for the uncertainty in the final result.

Conclusions:

The vapour pressure of BMH was determined using the static method at 20°C and was found to be: p (20°C) = 0.33 ± 0.02 Pa = (2.4 ± 0.2) x 10-3 mm Hg.

Description of key information

The vapour pressure of BMH was determined using the static method at 20°C and was found to be: p (20°C) = 0.33 ± 0.02 Pa = (2.4 ± 0.2) x 10-3 mm Hg.

Key value for chemical safety assessment

Vapour pressure:

0.33 Pa

at the temperature of:

20 °C