Betaine

Density

Link to relevant study record(s)

Reference

Endpoint:

relative density

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12/2004

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

The methodology does not follow the OECD guideline. The study is used to measure the bulk-weight of crystals. However, it was considered to be suitable for measuring the density of the solid substance. The test is performed in the manufacturer's certified (ISO 9001) laboratory. Also the analysis report is well documented.

Reason / purpose for cross-reference:

reference to other study

Principles of method if other than guideline:

The bulk-weight of crystals is determined by weighting a known volume of the sample at a controlled room temperature. The sample is placed in a graduated cylinder (volume 500 ml) and the weight of the sample is recorded with a tared scale (+/- 0,1 g accuracy). Before each measurement, the volume of the graduated cylinder is calibrated by filling it up with distilled water and by measuring the temperature and the mass of the filling.

The bulk-weight of crystals is calculated (dimension g/l) by the following equation:
Bulk-weight= m(sample)/V(graduated cylinder)*1000 g/l; where m = weight of crystals, g; V = calibrated volume of the cylinder, ml

Calibration of the graduated cylinder volume:
Cylinder is placed on a tared scale and filled up with water. The temperature of water is measured and the weight of water is recorded. The volume of the cylinder is calculated with the following equation:
V = m(water)/density of water at 20 C, where m= mass of water, g; Density of water ( 20C)= 0,9982071 g/ml (Handbook value: CRC 52nd Ed.(1971)).

The results are given as bulk-density (kgdm-3), and the relative density is calculated by diving the measured bulk-weight with the density of water at 4 C. The results are given in the attached table (section any information on materials and methods incl. tables).

GLP compliance:

no

Remarks:

Manufacturer's own laboratory, which has an ISO 9001 quality certificate

Type of method:

other: Bulk-weight of crystals

Type:

relative density

Density:

0.7 - 0.77

Temp.:

22 °C

Conclusions:

The Bulk-density of the substance was measured by weighting a known volume of the sample at room temperature.The measurement was repeated six times. The relative density was calculated by dividing the measured bulk-weight with the water density at 4 C. As a result, the bulk-weight (kgdm-3) and relative density were reported. The relative density of the substance varied between 0.7-0.77 (standard deviation is 0.03).

Executive summary:

The Bulk-density of the substance was measured by weighting a known volume of the sample at room temperature.The measurement was repeated six times. The relative density was calculated by dividing the measured bulk-weight with the water density at 4 C. As a result, the bulk-weight (kgdm-3) and relative density were reported. The relative density of the substance varied between 0.7-0.77 (standard deviation is 0.03).

Description of key information

The bulk-density of the substance was determined by weighting a known volume of the sample at a controlled temperature. The relative density of the substance was calculated by dividing the measured bulk-weight with the density of water at 4°C. The study was performed in the manufacturer's laboratory which has an ISO 9001 quality certificate.

Key value for chemical safety assessment

Relative density at 20C:

0.74