Registration Dossier

Physical & Chemical properties

Vapour pressure

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The vapour pressure is estimated less than 0.18 Pa at 25 °C (estimation).

Key value for chemical safety assessment

Additional information

The value of vapour pressure is estimated based on the study reports of mixture ''Sulfuric acid, mono-C12 -18-alkyl (even numbered) esters, sodium salts'' and ''sodium dodecyl sulphate''.

According to the theoretical principle of Raoult’s law, the vapour pressure of mixture is equal to the mole-fraction-weighted sum of the components' vapour pressures:

ptot= ∑ pixi

 

The vapour pressure of mixture should be lower than the vapour pressure of the component which has the highest vapour pressure in its pure form.

 

Therefore the vapour pressure of ''Sulfuric acid, mono-C12 -18-alkyl (even numbered) esters, sodium salts'' should be lower than the vapour pressure of ''sodium dodecyl sulphate C12''. This estimation is more reliable than the Grain-Watson calculation with the substance C12 -18 sodium salts itself (result: < 18 Pa), which also is taken into account in the weight of evidence approach.