Oxalacetic acid

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2017-03-09 to 2017-04-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7200 (Melting Point / Melting Range)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

capillary method

Key result

Melting / freezing pt.:

153.5 °C

Atm. press.:

1 013.25 hPa

Decomposition:

yes

Decomp. temp.:

>= 153.5 °C

During the preliminary test using a linear heating rate of 10 °C/min the phase transition of test item was observed at 163 °C.

In the main test using a linear heating rate of 0.5 °C/min the melting point of Oxaloacetic acid was determined to be 153.5 °C (426.6 K).

At the end of each measurement the samples in the capillary tube were melted, their color became yellow and moved to the upper part of the capillary. Thus, it was concluded that the substance decompose after melting.

Table: Measured temperatures corresponding to the melting point of Test Item (three experiments (I, II, III) with three parallel samples each (1, 2, 3))

Sample	Temperature (°C)	Mean (°C)	Standard Deviation	Confidence interval (95 %)
I /1	155.3	153.5	1.21	1.01
I /2	152.3
I /3	152.2
II /1	152.7
II /2	152.6
II /3	*-
III /1	153.6
III /2	154.9
III /3	154.2

* Measurement error

 

Conclusions:

Applying 0.5 °C/min heating rate in the capillary method, the melting point of the test item was determined to be 153.5 °C (426.6 K).

Executive summary:

A study was conducted according to OECD TG 102, Regulation (EC) No. 440/2008 method A.1 and EPA OPPTS 830.7200 to determine the melting point of the test item using the capillary method. In a preliminary test using a linear heating rate of 10 °C/min the phase transition of the test item was observed at 163 °C. For the main test, a small amount of test item was charged in capillary glass tubes and packed tightly to obtain a filling level of approximately 5 mm. Three capillaries were prepared. Heating was started from 130 °C with temperature rise of 0.5 °C/min. The melting point of the test item was determined to be 153.5 °C at 1013.25 hPa. At the end of each measurement the samples in the capillary tube were melted, their color became yellow and moved to the upper part of the capillary. Thus, it was concluded that the substance decompose after melting. The decomposition temperature was stated to be >= 153.5 °C.

Description of key information

The melting point of the test item was determined to be 153.5 °C at 1013.25 hPa.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

153.5 °C

Additional information

A study (reference 4.2-1) was conducted according to OECD TG 102, Regulation (EC) No. 440/2008 method A.1 and EPA OPPTS 830.7200 to determine the melting point of the test item using the capillary method. In a preliminary test using a linear heating rate of 10 °C/min the phase transition of the test item was observed at 163 °C. For the main test, a small amount of test item was charged in capillary glass tubes and packed tightly to obtain a filling level of approximately 5 mm. Three capillaries were prepared. Heating was started from 130 °C with temperature rise of 0.5 °C/min. The melting point of the test item was determined to be 153.5 °C at 1013.25 hPa. At the end of each measurement the samples in the capillary tube were melted, their color became yellow and moved to the upper part of the capillary. Thus, it was concluded that the substance decompose after melting. The decomposition temperature was stated to be >= 153.5 °C.