Uronium hydrogen sulphate

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

Target and source substances are highly similar, both structurally and chemically.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

GLP compliance:

no

Type of method:

dynamic method

Temp.:

20 °C

Vapour pressure:

670 Pa

Temp.:

25 °C

Vapour pressure:

900 Pa

Temp.:

50 °C

Vapour pressure:

2 900 Pa

Temperature / °C	Vapour pressure / hPa
37.5	10.0
50.5	29.9
63.6	46.1
71.6	60.0
76.5	70.0
96.5	90.3

Conclusions:

VP = 900 Pa at 25 °C

Executive summary:

The vapour pressure of uronium hydrogen sulphate was determined according to OECD guideline 104 (dynamic method):

670 Pa at 20 °C

900 Pa at 25 °C

2900 Pa at 50 °C

Description of key information

The vapour pressure of urea sulfate was determined to be 900 Pa at 25 °C.

However this relatively high value is probably due to the presence of water as additive (ca. 20%).

Key value for chemical safety assessment

Vapour pressure:

0.1 Pa

at the temperature of:

20 °C

Additional information

The vapour pressure of uronium hydrogen sulfate was determined according to OECD guideline 104 (dynamic method):

670 Pa at 20 °C

900 Pa at 25 °C

2900 Pa at 50 °C

Taken into account that the vapour pressure of urea and sulfuric acid are lower than 0.1 Pa, the relative high value of uronium hydrogen sulfate is probably due to the presence of water as additive (ca. 20%), because the vapour pressure of pure water is ca. 2.3 kPa at 20°C. Thus the results obtained of Uronium hydrogen sulphate cannot be considered relevant; therefore the key value for chemical safety assessment are the vapour pressure of urea and sulfuric acid.