[humble]

Hello, guys. Maybe it's some stupid question, but is there any one math's formula to calculate the approximate flash point of two oil fractions in open cup? Cause i found some one for close cup, but can't find for open.
Thanks.

[Enthalpy]

Welcome, humble!

Do you want to estimate the flash point of a mixture from the proportions and from the experimental flash points of each component?

I'd take the difference between open cup and closed cup for both components and extrapolate it for the mixture. Taking only the lightest component if they are very different, or a weighed sum if the vapour pressure is similar.

[humble]

Maybe, i asked some wrong question, sorry

I don't need math's formula. But i need some properties, on which the flash points in open cup depends on.
So, can i take the content of each component in mixture and, for example, the boiling points of each component?