Praseodymium trichloride

Appearance / physical state / colour

Administrative data

Endpoint:

appearance / physical state / colour

Type of information:

other: Visual inspection

Adequacy of study:

weight of evidence

Study period:

16 June 2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Information taken from a GLP-compliant study report on melting point in which the appearance and physical state of the test item was described based on visual inspection.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

16 June 2017 - 2 November 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Melting / freezing pt.:

> 600 °C

Atm. press.:

101.325 kPa

Decomposition:

no

Sublimation:

no

Remarks on result:

other: No melting point was recorded up to 600°C.

The first assay was not taken into account since a too big quantity of test item was weighed and the subsequent graph was unreliable.

Assay No. 2 (14.23 mg test item, isotherm at 25°C for 5 min, heating ramp: 25°C to 600°C at 10°C/min):

Several endothermic peaks were recorded between about 80 and 110°C, between about 125 and 215°C, and one additional endothermic peak was observed at 275°C. Two thin exothermic peaks were observed from 400°C to 425°C. After the assay, the powder was pale green and seemed dehydrated. No melting point of the test item was recorded up to 600°C.

Assay No. 3 (8.74 mg test item, isotherm at 25°C for 5 min, heating ramp: 25°C to 600°C at 10°C/min):

The third assay was similar to the second one.

Several endothermic peaks were recorded between about 80 and 110°C, between about 130 and 220°C, and a single endothermic peak was observed at 275°C. Two thin exothermic peaks were observed from 400°C to 425°C. After the assay, the powder was pale green and seemed dehydrated. No melting point of the test item was recorded up to 600°C.

The endothermic peaks are most likely due to consequent dehydration steps (e.g., solubilisation of the test material in its hydration water and consequent loss of hydration water). This was not reported in the study report but is a common observation in melting point studies with hydrated rare earth salts.

Conclusions:

The melting behaviour of praseodymium trichloride heptahydrate was assessed according to the EU A.1 method and OECD test guideline 102 in compliance with GLP using Differential Scanning Calorimetry (DSC). No melting point of the test item was recorded up to 600°C.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Visual inspection

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

trichloropraseodymium; heptahydrate

Cas Number:

10025-90-8

Molecular formula:

PrCl3.7H2O

IUPAC Name:

trichloropraseodymium; heptahydrate

Test material form:

solid: particulate/powder

Details on test material:

- Name of the test material (as in the report): praseodymium trichloride heptahydrate
- Physical state: solid
- Appearance: green crystalline powder
- Further information on test material confidential.

Results and discussion

Physical state at 20°C and 1013 hPa:

solid

Form / colour / odour

Form:

solid: crystalline

Colour:

green crystalline powder

Substance type:

inorganic

Applicant's summary and conclusion

Conclusions:

Praseodymium trichloride (heptahydrate form) is concluded to be a green crystalline powder under ambient conditions.