# How to calculate the gas-liquid interaction for dissolved HNO3 in water with air?

I have to face the following problem: I have got $\ce{HNO3}$ dissolved in water (roughly $\pu{50\%}$) and I want to know how much $\ce{HNO3}$ will be in the air directly above it. I got classes about liquid-gas phases, but it was a long time ago and therefore I am not capable anymore to engage such a question.
As far as I can recall the pressure and temperature are important, which are $\pu{1 atm}$ and $\pu{20-25^oC}$ (but I want to calculate it for a range between $\pu{20-100^oC}$). I can imagine that it might be hard due to the fact that a part of the $\ce{HNO3}$ will split into ions $\ce{H+}$ and $\ce{NO3-}$ (till it reach its pKa), so that will give an equilibrium towards the liquid phase. But in the end there must be some $\ce{HNO3}$ in the air due to gas-liquid equilibrium.
Edit: During further investigation I found out that the problem is even more complicated since $\ce{HNO3}$ will split into $\ce{NO}$, $\ce{NO2}$ and $\ce{N2O4}$ (nitrous gases). If possible I want all the concentrations of these gases at those temperatures.