Pseudo components are a way of defining new components that are a mixture of other, real, components. For example: there is no component called
iso-pentane. It is just a mixture of the two other isomers of normal pentane: methyl butane and dimethyl propane (neo pentane) in some defined proportion.
The ISO6976 program allows you to create such pseudo components very simply:
Pseudo components are also useful for blending calculations. Imaging that you are blending five different gases with many different components, it can become a bit of a nightmare. With Pseudo Components all you need do is set up each gas as a pseudo component as indicated above and then when you want to blend create a gas using the pseudo components and then blend these to get your results.
There is no limit to the number of Pseudo Components you can create.
Pseudo components do introduce small rounding errors of the order of 1 part in 10^12. This is miniscule when compared to the overall accuracy of the ISO6976 procedure itself and can be ignored.