1,4-naphthoquinone

Melting point / freezing point

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

melting point/freezing point

Type of information:

other: reliable handbook data

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Qualifier:

no guideline followed

Principles of method if other than guideline:

The use of secondary sources of data is acceptable when they are based on a critical evaluation of peer-reviewed data and a consequent selection of a reliable and representative values for the properties under investigation.

The introduction to the CRC Handbook of Chemistry and Physics states that data for physical constants have been taken from many sources, including both compilations and the primary literature. Where conflicts were found, the value deemed most reliable was chosen. Therefore, although the method used is not known, the values presented here are acceptable as they are considered to be from a reliable secondary source of phys chem. data.

GLP compliance:

not specified

Type of method:

other: unknown method

Melting / freezing pt.:

128.5 °C

Atm. press.:

101.3 kPa

Conclusions:

The test substance melting point was determined to be 128.5°C based on a result taken from peer reviewed handbook data.

Reference 2

Endpoint:

melting point/freezing point

Type of information:

other: authoritative database

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Qualifier:

no guideline followed

Principles of method if other than guideline:

Data detailed in the International Chemical Safety Card (ICSC) for 1,4-Naphthoquinone. These cards are meant as a way of summarising essential information on chemical substances; and were jointly developed by the IPCS and the European Commission.

The cards are then peer-reviewed by a committee consisting of internationally- recognized experts who take into account advice given by manufacturers, workers' representatives and poisons centres.

The use of secondary sources of data is acceptable when they are based on a critical evaluation of peer-reviewed data and a consequent selection of a reliable and representative values for the properties under investigation.

Based on the above information, although full experimental details are unknown, the values presented here are acceptable as they are considered to be from a reliable secondary source of phys chem. data.

GLP compliance:

not specified

Type of method:

other: unknown method

Melting / freezing pt.:

126 °C

Conclusions:

The test substance melting point was determined to be 126°C based on a result taken from the International Chemical Safety Card for the substance.

Description of key information

A total of two melting point values (126 and 128.5°C) are available for this substance based on reliable handbook data. As these values are very similar, the higher value of 128.5°C has been selected as the key value for chemical safety assessment as it is directly listed in a physical properties handbook.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

128.5 °C