N-(2-{[C16-18 (even numbered) alkanoyl]amino}ethyl)-N-(2-hydroxyethyl)[C16-18 (even numbered) alkylamide

Density

Link to relevant study record(s)

Reference

Endpoint:

relative density

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19 July 2017 - 01 June 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study was conducted in accordance with international guidelines and in accordance with GLP. All guideline validity criteria were met.

Qualifier:

according to guideline

Guideline:

EU Method A.3 (Relative Density)

Version / remarks:

Regulation (EC) 440/2008 of 30 May 2008

Deviations:

yes

Remarks:

Study was performed at 19.5 °C not 20.0 °C (as per guideline). Typical thermal expansion coefficients of solids and the volumetric expansion of stainless steel are of the order of 10-5 °C-1. A temperature delta of 0.5 °C is expected to be negligible.

Qualifier:

according to guideline

Guideline:

OECD Guideline 109 (Density of Liquids and Solids)

Version / remarks:

02 October 2012

Deviations:

yes

Remarks:

Study was performed at 19.5 °C not 20.0 °C (as per guideline). Typical thermal expansion coefficients of solids and the volumetric expansion of stainless steel are of the order of 10-5 °C-1. A temperature delta of 0.5 °C is expected to be negligible.

GLP compliance:

yes (incl. QA statement)

Type of method:

air comparison pycnometer (for solids)

Key result

Type:

relative density

Density:

1.01 other: Dimensionless.

Temp.:

19.5 °C

Remarks on result:

other: Study was performed at 19.5 °C not 20.0 °C (as per guideline).

Remarks:

Typical thermal expansion coefficients of solids and the volumetric expansion of stainless steel are of the order of 10-5 °C-1. A temperature delta of 0.5 °C is expected to be negligible.

Evaluation of Data:

The density of a substance is the quotient of the mass and the volume of that substance at a specific temperature. The SI unit is kg/m³. 1 g/cm³ corresponds to 1000 kg/m³. The density (ρ) of the test item was calculated using the following equations:

 

Equation 1:

V_ref= V_cal/(P₁/P₂– P₃/P₄)

 

Equation 2:

V_cell= V_ref. ((P₁/P₂) - 1)

 

Equation 3:

V_sample= V_cell– V_ref. ((P_1(sample)/P_2(sample)) - 1)

 

Equation 4:

row = 1000 m/V_sample

 

where:

P₁, P₂= Pressure readings in the calibration procedure without calibration sphere (psig)

P₃, P₄= Pressure readings in the calibration procedure with calibration sphere (psig)

P_1(sample), P_2(sample)= Pressure readings with the sample cell containing test item (psig)

V_cal= Volume of the calibration sphere (cm³)

V_ref= Volume of the reference cell (cm³)

V_cell= Volume of the sample cell (cm³)

V_sample= Volume of the test item (cm³)

m = Mass of test item (g)

 

The relative density of solids or liquids is the ratio between the mass of a volume of substance to be examined determined at 20 °C, and the mass of the same volume of water determined at 4 °C. Relative density has no dimensions. The density of water determined at 4 °C is 999.97 kg/m3 (as published by the CRC Handbook of Chemistry and Physics, 94th Edition 2013-2014). The relative density (D²⁰₄) was calculated using the following equation:

 

Equation 5:

D²⁰₄= ρ / (999.97 kg/m³)

 

 

Calibration:

The pressure readings and the calculated volume for the reference and sample cells are shown in the following table:

Table 2:          

Determination	P1(psig)	P2(psig)	P3(psig)	P4(psig)	Reference cell volume (cm^3)	Sample cell volume (cm^3)
1	17.246	6.528	17.260	8.554	90.628	148.797
2	17.209	6.516	17.325	8.586	90.753	148.929
3	17.200	6.514	17.202	8.523	90.907	149.130
Mean					90.763	148.952

Vcal = 56.559 cm3

Calibration was performed at 18.9 ± 0.5 °C

As the reference cell volume and sample cell volume were within the defined tolerance (90.953 ± 1.0 cm3 and 149.225 ± 1.0 cm3 for the reference and sample cell volumes respectively) the gas comparison pycnometer was therefore considered acceptable for use.

Density Determination:

The pressure readings, calculated volumes and density values obtained for the test item are shown in Table 3:

Table 3:       

Determination	Test	P1(sample)(psig)	P2(sample)(psig)	Volume (cm^3)	Density (kg/m^3)	Mean density (kg/m^3)
1	A	17.002	7.106	22.554	1.002 x 10^3	1.005 x 10^3
	B	17.026	7.115	22.522	1.004 x 10^3
	C	17.026	7.113	22.461	1.006 x 10^3
2	A	17.025	7.159	23.870	1.006 x 10^3	1.006 x 10^3
	B	17.011	7.153	23.866	1.006 x 10^3
	C	16.987	7.142	23.839	1.007 x 10^3

Sample determinations were performed at 19.5 ± 0.5 °C

Vcal = 56.559 cm3

Mean density  :  1.01 x 103 kg/m3

Relative density  :  1.01

Temperature  :  19.5 ± 0.5 °C

Discussion:

Duplicate determinations were performed to ensure a reproducibility of less than ± 20 kg/m3 was obtained.

The mass density of a substance varies with temperature and pressure and this variance is typically negligible for solids.  Increasing the temperature of a substance may decrease its density by increasing the volume of that substance.  Typical thermal expansion coefficients of solids are in the order of 10-5 °C-1, and the volumetric expansion of stainless steel (used as calibration spheres) at 20 °C is approximately 5.2 x 10-5 °C-1.  Therefore, a change in temperature of several degrees will have no significant effect on the volume and hence the density of a solid substance.  Therefore, it was considered that the difference in temperature between 20.0 °C and normal laboratory conditions did not have a significant effect on the determined density, and therefore the calculated relative density.

Conclusion:

The density of the test item has been determined to be 1.01 x 103 kg/m3 at 19.5 ± 0.5 °C (relative density: 1.01).

Conclusions:

The density of the test item has been determined to be 1.01 x 103 kg/m3 at 19.5 ± 0.5 °C (relative density: 1.01).

Executive summary:

EU Method A.3. – The relative density of the test item was determined utilising an gas comparison pycnometer.  The procedure employed was designed to be compatible with Method A.3., Relative Density, of Commission Regulation (EC) No 440/2008 of 30 May 2008.

Two determinations were carried out.  An instrumentation check was performed by measuring of the volume of the reference sphere.  Aliquots of test item (22.5 – 24.0 g) were placed in the measuring cell.  The density of the test item was determined.  This determination was performed in triplicate at 19.5 °C ± 0.5 °C to acquire a mean value.

The relative density (D₄²⁰) of the test item was calculated to be 1.01, based on the ratio of the measured density of the test item relative to the density of water a 4 °C i.e.;

D₄²⁰  = density_{test item}/density_water

where:

test item = density of test item at 19.5 °C (g/cm3)

water = density of water at 4.0 °C (g/cm3)

Note: The mass density of a substance varies with temperature and pressure and this variance is typically negligible for solids.  Typical thermal expansion coefficients of solids are in the order of 10-5 °C-1, and the volumetric expansion of stainless steel (used as calibration spheres) at 20 °C is approximately 5.2 x 10-5 °C-1.  Thus, a change in temperature of several degrees will have no significant effect on the volume and hence the density of a solid substance.  It was considered that the difference in temperature between 20.0 °C and normal laboratory conditions did not have a significant effect on the determined density, and therefore the calculated relative density.

Description of key information

Density: Relative Density = 1.01; EU Method A.3.; R. Butler (2018)

Key value for chemical safety assessment

Relative density at 20C:

1.01

Additional information

EU Method A.3. – The relative density of the test item was determined utilising an gas comparison pycnometer.  The procedure employed was designed to be compatible with Method A.3., Relative Density, of Commission Regulation (EC) No 440/2008 of 30 May 2008.

Two determinations were carried out.  An instrumentation check was performed by measuring of the volume of the reference sphere.  Aliquots of test item (22.5 – 24.0 g) were placed in the measuring cell.  The density of the test item was determined.  This determination was performed in triplicate at 19.5 °C ± 0.5 °C to acquire a mean value.

The relative density (D420) of the test item was calculated to be 1.01, based on the ratio of the measured density of the test item relative to the density of water a 4 °C i.e.;

D420 = density_{test item}/density_water

where:

test item = density of test item at 19.5 °C (g/cm3)

water = density of water at 4.0 °C (g/cm3)

Note: The mass density of a substance varies with temperature and pressure and this variance is typically negligible for solids.  Typical thermal expansion coefficients of solids are in the order of 10-5 °C-1, and the volumetric expansion of stainless steel (used as calibration spheres) at 20 °C is approximately 5.2 x 10-5 °C-1.  Thus, a change in temperature of several degrees will have no significant effect on the volume and hence the density of a solid substance.  It was considered that the difference in temperature between 20.0 °C and normal laboratory conditions did not have a significant effect on the determined density, and therefore the calculated relative density.