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Physical & Chemical properties

Melting point / freezing point

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Link to relevant study record(s)

Reference
Endpoint:
melting point/freezing point
Type of information:
other: statistical review
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Statistical approach to available data, however, no attempt was made weight individual reported melting points for quality.
Qualifier:
no guideline followed
Principles of method if other than guideline:
The mean melting point was calculated for multiple measurements reported in the literature.
GLP compliance:
no
Type of method:
other: statistical review
Melting / freezing pt.:
24.1 °C
Atm. press.:
ca. 1 atm
Decomposition:
no
Sublimation:
no
Remarks on result:
other: 95%C.I. 23.67-24.54°C
Conclusions:
The mean literature melting point for cyclohexanol is 24.10 °C (23.67 – 24.54 °C). In addition to experimental uncertainty in the temperature measurement, the above statistical value can be expected to encompass variation due to sample purity, and unrecognised polymorphism. Bias introduced by data recycling cannot be excluded, but has been attempted to be controlled for, although without inspection of every literature reference.

Description of key information

24.10 °C (23.67 – 24.54 °C), statistical review 
25.5-25.6 °C, Nitta 1948
25.62 °C, Hennings 1962
25.90 °C ±0.03 °C, Adachi 1968

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:
24.1 °C

Additional information

A survey of available literature data was carried out for the melting point. The potential data sources were restricted to two bibliographic databases, augmented by data from studies previously identified as having high-quality results for other physico-chemical endpoints. No attempt was made to weight individual studies by reliability, instead a statistical approach was taken. Data from obvious secondary sources, and multiple reports of a numerically equivalent melting point by the same authors, were discarded as potential sources of bias due to data recycling. The mean melting point and confidence interval was calculated.

Three references with known high purity (Nitta, Hennings, Adachi) were reported with melting point somewhat higher than the mean value. This could be a reflection of melting point depression due to impurities, or potentially a result of unrecognised polymorphs in the literature.

The mean value is taken forward for the purposes of risk assessment, as being most representative of the commercial substance. The available data is considered to be relevant, reliable, and adequate for risk assessment purposes. The endpoint is considered complete, in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.1.1.