3,7-dimethylocta-1,6-diene

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

September 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted according to OECD 104 and EU A.4 guidelines, under GLP without deviation and with certificate of analysis included.

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

static method

Temp.:

20 °C

Vapour pressure:

409 Pa

Temp.:

25 °C

Vapour pressure:

532 Pa

The calculation results are presented in the following table:

Calculated values for 1/T and log P

n	t	P	T	1/T	log P
	°C	mbar = hPa	K	1/K	log P (Pa)
1	20.2	3.90	293.35	0.00340890	2.5911
2	27.0	5.50	300.15	0.00333167	2.7404
3	27.2	5.60	300.35	0.00332945	2.7482
4	27.4	5.70	300.55	0.00332723	2.7559
5	33.2	7.60	306.35	0.00326424	2.8808
6	34.6	8.50	307.75	0.00324939	2.9294
7	42.3	12.10	315.45	0.00317007	3.0820
8	49.6	16.80	322.75	0.00309837	3.2253
9	44.8	14.0	317.95	0.00314515	3.1461
10	53.6	20.90	326.75	0.00306044	3.3201
11	52.6	19.00	325.75	0.00306984	3.2788
12	59.0	24.70	332.15	0.00301069	3.3927
13	61.7	28.30	334.85	0.00298641	3.4518
14	65.0	32.00	338.15	0.00295727	3.5051
15	59.3	26.20	332.45	0.00300797	3.4183
16	54.2	20.90	327.35	0.00305483	3.3201
17	52.6	19.60	325.75	0.00306984	3.2923
18	49.0	17.00	322.15	0.00310414	3.2304
19	47.6	15.80	320.75	0.00311769	3.1987
20	43.3	13.50	316.45	0.00316006	3.1303
21	40.0	11.60	313.15	0.00319336	3.0645

22	31.3	7.80	304.45	0.00328461	2.8921
23	22.5	5.50	295.65	0.00338238	2.7404

The parameters for the linear regression are presented in the following table:

Linear Regression Parameters

Parameter	Value
Slope B	-1984.32
Intercept A	9.381
Correlation coefficient r	-0.9966

Using the equation log P = B*1/T + A, values of vapour pressure at room temperature and boiling point were calculated as:

Calculated Values for vapour pressure

Parameter	Value	Unit
Vapour Pressure (20 °C)	409	Pa
Vapour Pressure (25 °C)	532	Pa
Boiling Point	453.53	K
Boiling Point	180.38	°C

 

Conclusions:

Using the static method according to OECD 104 guideline and EU method A.4, vapour pressures of 409 Pa at 20 °C and 532 Pa at 25 °C were estimated.
These values were calculated from the regression of 21 individual measurements.

Executive summary:

The vapour pressure of the test item was calculated as 409 Pa at 20 °C and as 532 Pa at 25.0 °C.

The correlation coefficient r being -0.9966, the linear regression is very good and the results are considered as valid. No observations were made which might cause doubts concerning the validity of the study outcome.

Description of key information

Using the static method, vapour pressures of 409 Pa at 20 °C and 532 Pa at 25 °C were determined.
These values were calculated from the regression of 23 individual measurements.

Key value for chemical safety assessment

Vapour pressure:

409 Pa

at the temperature of:

20 °C

Additional information

A key study was conducted according to OECD 104 and EU A.4 guidelines, under GLP without deviation and with certificate of analysis included. Therefore the value obtained in this study may be proposed as a key value.