4-acetyl-2-methylbenzoic acid

Density

Administrative data

Endpoint:

bulk density

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 109 (Density of Liquids and Solids)

Version / remarks:

2012

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

air comparison pycnometer (for solids)

Test material

Test material information

Constituent 1

Reference substance name:

4-acetyl-2-methylbenzoic acid

EC Number:

856-079-4

Cas Number:

55860-35-0

Molecular formula:

C10H10O3

IUPAC Name:

4-acetyl-2-methylbenzoic acid

Test material form:

solid: particulate/powder

Results and discussion

Density

Key result

Type:

bulk density

Density:

1.35 g/cm³

Temp.:

20 °C

Any other information on results incl. tables

The density of the test substance was determined with the gas comparison pycnometer method. A Multi-Pycnometer from Quantochrome (Syosset, USA) was used in this study. The instrument can be pressurised with helium and consists of two interlinked reference and sample cells of fixed volume. The volumes of the two cells were confirmed prior to the test through the use of a stainless steel calibration sphere of certified volume. The sample analysis was then performed by recording the pressure drop for the pressurised reference cell when the additional volume of the sample cell containing an accurately weighed aliquot of test substance was added, from which the volume of the test substance could be accurately calculated. The volume of the reference cell was determined from four pressure readings obtained in the calibration procedure with the stainless steel calibration sphere. Aliquots of the test substance of 20.5794 and 21.3753 g were weighed into the sample cell and placed into the pycnometer. Triplicate pressure pressure readings were taken after pressurising the reference cell of known voume and then switching to the sample cell. The reference cell and sample cell volumes were within the defined tolerance (90.953 ± 1.0 cm3 and 149.225 ± 1.0 cm3) and the gas comparison pycnometer was considered acceptable for use. The overall mean density was determined to be 1.35 g/cm3.

Table 1: Gas comparison pycnometer calibration results

Replicate	P1 (psig)	P2 (psig)	P3 (psig)	P4 (psig)	Reference cell volume (cm3)	Sample cell volume (cm3)
1	17.150	6.496	17.033	8.439	90.972	149.202
2	17.038	6.457	17.063	8.456	91.102	149.288
3	17.058	6.465	17.035	8.444	91.062	149.206

Table 2: Measurement results for test substance

Determination	Test	P1 (psig)	P2 (psig)	Volume (cm3)	Density (kg/m3)
1	A	17.078	6.907	15.162	1.36 E03
1	B	17.124	6.927	15.207	1.35 E03
1	C	17.009	6.879	15.159	1.36 E03
2	A	17.003	6.895	15.760	1.36 E03
2	B	17.104	6.938	15.827	1.35 E03
2	C	17.056	6.918	15.809	1.35 E03

Applicant's summary and conclusion

Conclusions:

The mean density of the substance was determined to be 1.35 g/cm3 at 20 °C.

Executive summary:

The density of the substance was determined under GLP to OECD TG 109 using the gas comparison pycnometer method. The density of the test substance was determined with the gas comparison pycnometer method. A Multi-Pycnometer from Quantochrome (Syosset, USA) was used in this study. The instrument can be pressurised with helium and consists of two interlinked reference and sample cells of fixed volume. The volumes of the two cells were confirmed prior to the test through the use of a stainless steel calibration sphere of certified volume. The sample analysis was then performed by recording the pressure drop for the pressurised reference cell when the additional volume of the sample cell containing an accurately weighed aliquot of test substance was added, from which the volume of the test substance could be accurately calculated. The volume of the reference cell was determined from four pressure readings obtained in the calibration procedure with the stainless steel calibration sphere. Aliquots of the test substance of 20.5794 and 21.3753 g were weighed into the sample cell and placed into the pycnometer. Triplicate pressure pressure readings were taken after pressurising the reference cell of known voume and then switching to the sample cell. The reference cell and sample cell volumes were within the defined tolerance (90.953 ± 1.0 cm3 and 149.225 ± 1.0 cm3) and the gas comparison pycnometer was considered acceptable for use. The overall mean density of the test substance was determined to be 1.35 g/cm3.