Palladium dihydroxide

Melting point / freezing point

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Compliant, guideline study, available as unpublished report, acceptable with restrictions

Qualifier:

according to guideline

Guideline:

other: OECD 102/A1 Melting Freezing Temperature

Principles of method if other than guideline:

Differential scanning calorimetry (DSC) using the procedure specified in ASTM E537-86

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Melting / freezing pt.:

> 450 °C

The resulting powder residue on completion of each determination indicated the absence of any phase transition (ie melting) of the test item during heating up to 723K (>450 °C). The shallow, borad endotherm observed at approximately 60 to 140 °C in each determination was atrributed to dehydration of the test item, it having been supplied as a hydrate

Conclusions:

The melting/freezing point of palladium monoxide is > 450 °C

Executive summary:

This is a GLP compliant, guideline study which is considered suitable for use as the key study for this endpoint. The melting/freezing point of palladium monoxide is > 450°C

Reference 2

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 September 2010 to 2 December 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Compliant, guideline study, available as unpublished report, acceptable with restrictions

Qualifier:

according to guideline

Guideline:

other: OECD 101/A1 Melting Freezing Temperature

Principles of method if other than guideline:

Differential scanning calorimetry (DSC) using the procedure specified in ASTM E537-86

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Melting / freezing pt.:

60

Decomposition:

yes

Decomp. temp.:

60 °C

Remarks on result:

other: no melting below 450°C

As a result of the low rate of enthalpy change during decomposition, the onset temperatrue can only be approximated.

Similar thermographic profiles were obtained using air and nitorogen atmospheres; this indicates that the observed decomposition is probably thermal and not oxidative

Conclusions:

Palladium dihydroxide (solid only) decomposed at approximately 60 °C with no definitive signs of melting below 450°C

Executive summary:

This is a GLP compliant, guideline study which is considered suitable for use as the key study for this endpoint. Palladium dihydroxide (solid only) decomposed at 60 °C with no definitive signs of melting below 450°C

Description of key information

Palladium dihydroxide decomposed at 60°C with no definitive signs of melting below 450°C.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

450 °C

Additional information

Walker and White (2011) is a GLP compliant, guideline study which is considered suitable for use as the key study for this endpoint. Palladium dihydroxide decomposed at 60°C with no definitive signs of melting below 450°C.

Testing has also been conducted on a sample of ‘palladium monoxide (hydrate)’. Further assessment of the substance identity of the test item indicated that based on the analytical data this sample was the same substance as palladium dihydroxide. Studies conducted on the sample of ‘palladium monoxide (hydrate)’ are therefore included in the dossier for palladium dihydroxide. O'Connor and Woolley (2011) is a GLP compliant, guideline study considered suitable for use as the key study for this endpoint. The melting point of palladium monoxide (hydrated solid) is > 450°C.