Nickel oxalate

Melting point / freezing point

Administrative data

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2010-04-19 to 2010-06-02

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study performed according to OECD Guideline 102 (Melting point / Melting Range) and EU Method A.1 (Melting / Freezing Temperature) without deviation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

GLP compliance:

yes

Type of method:

other: differential scanning calorimetry (DSC)

Test material

Test material information

Constituent 1

Reference substance name:

nickel (II) oxalate dihydrate

IUPAC Name:

nickel (II) oxalate dihydrate

Constituent 2

Reference substance name:

6018-94-6

Cas Number:

6018-94-6

IUPAC Name:

6018-94-6

Details on test material:

- Name of test material (as cited in study report): nickel oxalate dihydrate
- Molecular formula (if other than submission substance): NiC2O4.2H2O
- Molecular weight (if other than submission substance): 182.7 g/mol
- Structural formula attached as image file (if other than submission substance): see Figure 1
- Physical state: light green-blue powder with lumps
- Analytical purity: no data
- Lot/batch No.: MC_NiOx_NOTOX_100302
- Expiration date of the lot/batch: 2011-03-15
- Stability under test conditions: stable
- Storage condition of test material: at room temperature in the dark

Results and discussion

Any other information on results incl. tables

In the preliminary experiment, from 75 °C upwards the weight of the sample decreased significantly. At 308 °C the sample weight had decreased by 25%. After the experiment, a black residue remained in the sample container (original colour: light green-blue). The change of the colour indicated reaction and/or decomposition of the test substance.

In Experiment I, a first endothermic peak was observed at 88.28 °C and a second endothermic peak at 250.99 °C.

Experiment II was performed in order to investigate the second endothermic effect observed in the first experiment. The second peak was observed at an onset temperature of 247.26 °C. This effect was most likely obtained due to evaporation of a small part of the test substance. A third endothermic effect was observed between 350 °C and 450 °C. The extrapolated onset temperature of the peak was 373.34 °C. After the experiment, a black residue remained in the sample container (original colour: light green-blue). The change of the colour indicated reaction and/or decomposition of the test substance.

Experiment III was performed with a closed lid to investigate the effects of evaporation. The first and second endothermic peaks were shifted to higher temperatures (162.07 °C and 289.46 °C, respectively) indicating that these processes were driven by evaporation. The third peak, however, was not shifted (379.97 °C), indicating reaction and/or decomposition was probably the reason for the effect. After the experiment, a black residue remained in the sample container (original colour: light green-blue). The change of the colour confirmed reaction and/or decomposition of the test substance.

To investigate the third endothermic effect, a lower heating rate of 5°C/minute was applied in the Experiment IV. The extrapolated onset temperature of the third endothermic effect was 339.67 °C (see DSC curve below). Shifting of the endothermic peak to lower temperature with lower heating rate, demonstrated that reaction and/or decomposition of the test substance was the reason for this endothermic effect. After the experiment, a black residue remained in the sample container (original colour: light green-blue).

Applicant's summary and conclusion

Conclusions:

Using differential scanning calorimetry, reaction and/or decomposition of the test substance was observed starting at a temperature of 200 °C (473K). Melting of the test substance was not observed below the temperature at which reaction and/or decomposition started. Based on this, the test substance has no melting temperature.