A mixture of isomers of branched tetracosane

Vapour pressure

Administrative data

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2 February 1995 and 15 March 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The work described was performed in compliance with the UK Principles of Good Laboratory Practice (The United Kingdom Compliance Programme, Department of Health 1989).

Type of method:

effusion method: vapour pressure balance

Test material

Test material information

Constituent 1

Reference substance name:

A mixture of isomers of branched tetracosane

EC Number:

417-060-2

EC Name:

A mixture of isomers of branched tetracosane

Cas Number:

151006-61-0

Molecular formula:

C24 H50

IUPAC Name:

A mixture of isomers of branched tetracosane

Results and discussion

Vapour pressure

Temp.:

25 °C

Vapour pressure:

0 Pa

Any other information on results incl. tables

RUN 1

A plot of Log10 (vapour pressure (Pa)) versus reciprocal temperature (1/T(K)) for Run 1 gives the following statistical data using an unweighed least squares treatment.

Slope : -4103.703

Standard deviation in slope : 53.385

Intercept : 10.944

Standard deviation in intercept : 0.144

The results obtained indicate the following vapour pressure relationship:

Log10 (Vp/Pa) = -4103.703/temp(K) + 10.944

The above yields a calculated vapour pressure at 298.15 with a common logarithm of

Log10 (Vp/Pa_ at 298.15 K = -2.820

RUN 2

A plot of Log10 (vapour pressure (Pa)) reciprocal temperature (1/T(K)) for Run 2 gives the following statistical data using an unweighed least squares treatment.

Slope : -5642.405

Standard deviation in slope : 42.573

Intercept : 15.176

Standard deviation in intercept : 0.118

The results obtained indicate the following vapour pressure relationship:

Log10 (Vp/Pa) = -5642.405/temp(K) + 15.176

The above yields a calculated vapour pressure at 298.15 with a common logarithm of

Log10 (Vp/Pa_ at 298.15 K = -3.749

RUN 3

A plot of Log10 (vapour pressure (Pa)) versus reciprocal temperature (1/T(K)) for Run 3 gives the following statistical data using an unweighed least squares treatment.

Slope : -2974.774

Standard deviation in slope : 160.250

Intercept : 7.562

Standard deviation in intercept : 0.459

The results obtained indicate the following vapour pressure relationship:

Log10 (Vp/Pa) = -2974.774/temp(K) + 7.562

The above yields a calculated vapour pressure at 298.15 with a common logarithm of

Log10 (Vp/Pa_ at 298.15 K = -2.415

RUN 4

A plot of Log10 (vapour pressure (Pa)) versus reciprocal temperature (1/T(K)) for Run 4 gives the following statistical data using an unweighed least squares treatment.

Slope : -5291.680

Standard deviation in slope : 21.981

Intercept : 14.352

Standard deviation in intercept : 0.063

The results obtained indicate the following vapour pressure relationship:

Log10 (Vp/Pa) = -5291.680/temp(K) + 14.352

The above yields a calculated vapour pressure at 298.15 with a common logarithm of

Log10 (Vp/Pa_ at 298.15 K = -3.396

RUN 5

A plot of Log10 (vapour pressure (Pa)) versus reciprocal temperature (1/T(K)) for Run 5 gives the following statistical data using an unweighed least squares treatment.

Slope : -5366.856

Standard deviation in slope : 37.770

Intercept : 14.589

Standard deviation in intercept : 0.108

The results obtained indicate the following vapour pressure relationship:

Log10 (Vp/Pa) = -5366.856/temp(K) + 14.589

The above yields a calculated vapour pressure at 298.15 with a common logarithm of

Log10 (Vp/Pa_ at 298.15 K = -3.412

Detailed results from all the runs can be found in Attachment 1.

RESULTS

Run	Log10 vapour pressure (Pa) at 25 deg C
1	-2.82
2	-3.749
3	-2.415
4	-3.396
5	-3.412
Mean (Runs 2, 4 and 5)	-3.519

Vapour pressure = 3.0E-4 Pa.

Applicant's summary and conclusion

Conclusions:

ALKANE 2 has been determined to have a vapour pressure of 3.0E-4 Pa at 25 Deg C.

Executive summary:

Runs 1 and 3 have not been used as it was evident that degassing was taking place.

The test material did not change in appearance under the conditions used during the determination.

The experimental procedure used complied with that specified in Method A4 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

ALKANE 2 has been determined to have a vapour pressure of 3.0E-4 Pa at 25 Deg C.