Potassium hexafluorophosphate

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1955

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

The study from 1955 is designed like OECD105: solution of substance with temperature controll, analytical measurement of substance.

Deviations:

yes

Remarks:

The study from 1955 is designed like OECD105: solution of substance with temperature controll, analytical measurement of substance. As a relevant difference, no pH was measured.

Type of method:

flask method

Specific details on test material used for the study:

Potassium hexafluorophosphate was recrystallized three times from alkaline aqueous solutions by the method of Woyski.
Gravimetric analvsis of the recrystallized product indicated a content of 100 %.

Key result

Water solubility:

8.35 other: weight percent

Conc. based on:

test mat.

Remarks:

pure potassium hexafluorophosphate

Temp.:

25 °C

pH:

ca.

Remarks on result:

other: literature doesn't describe a measured pH; it is not expectec that the substance itself influences pH

Water solubility:

7.3 other: weight percent

Conc. based on:

test mat.

Remarks:

pure potassium hexafluorophosphate

Temp.:

20.2 °C

Remarks on result:

other: literature doesn't describe a measured pH; it is not expectec that the substance itself influences pH

Conclusions:

The water solubiity of potassium hexafluorophosphte at 25° C is 8.35 weight percent.

Executive summary:

According to experimental published data (comparable to OECD105) the solubility of potassium hexafluorophosphte in water at 25° C is 8.35 weight percent.

Reference 2

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Justification for type of information:

The publicated experimental study describes analytical determinaten of water solubility not in detail.

Principles of method if other than guideline:

No guideline available at testing date, experimental work comparable to guideline

GLP compliance:

no

Type of method:

flask method

Specific details on test material used for the study:

Crystalline solid.
Elemental analysis: calculated: K 21.23, P 16.86, F 61.91 measured: K 21.36,. P 16.78, F 61.66.
After synthesis recrystallised from boiling water.

Key result

Water solubility:

0.432 other: mol/liter

Conc. based on:

test mat.

Temp.:

22.5 °C

pH:

ca. 7

Remarks on result:

other: pH not measured but stated that the salt reacts pH-neutral

Alkali salts of Phosphor hexafluorid react neutral in solution. Decomposition was not recognised during recrystallisation on platin vessels. Cold water solutions don't react with glas vessels during days.

No melting on heating up to 305°C;

Density d18/4: 2.591

Conclusions:

The water solubility of the substance was determined to be 0.432 mol/l at 22.5°C. (= 79,5 g/l with 184.06 g/mol)

Executive summary:

The water solubility of the substance was determined to be 0.432 mol/l at 22.5°C. (= 79,5 g/l with 184.06 g/mol)

Reference 3

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Justification for type of information:

The published experimental study describes analytical determination of water solubility not in detail.

Principles of method if other than guideline:

not described in detail

GLP compliance:

no

Specific details on test material used for the study:

Purity not specified.

Key result

Water solubility:

0.49 other: mol/l

Conc. based on:

test mat.

Temp.:

25 °C

Remarks on result:

not measured/tested

Conclusions:

Water solubility of 0.49 mol/l at 25°C was determined (=90.2 g/l with 184.06 g/mol).

Executive summary:

Water solubility of 0.49 mol/l at 25°C was determined (=90.2 g/l with 184.06 g/mol).

Description of key information

According to the key study Sarmousakis and Low, 1955, the water solubility was determined to be 83.5 g/kg (25 °C) and 73 g/kg (20.2 °C)

In a weigth of evidence approach, water solubiliy was determined to be 79.5 g/L (22.5 °C) and 90.2 (25 °C).

Key value for chemical safety assessment

Water solubility:

90.2 g/L

at the temperature of:

25 °C