Use the Clausius–Clapeyron equation: ln(P2/P1) = -ΔHvap/R × (1/T2 – 1/T1)
Rearrange to solve for the unknown vapor pressure: P2 = P1 × e^[-ΔHvap/R × (1/T2 – 1/T1)]
Use the Antoine equation when constants are available: log10(P) = A – B/(C + T)
Solve for vapor pressure from the Antoine equation: P = 10^(A – B/(C + T))
Use Raoult’s law for an ideal solution: Psolution = Xsolvent × P°solvent
For a mixture, calculate total vapor pressure: Ptotal = Σ(Xi × P°i)
Convert temperature to Kelvin when required: K = °C + 273.15
Use consistent pressure units throughout the calculation
Use the latent heat of vaporization, temperature, and reference pressure when applying thermodynamic equations
Substitute the known values into the chosen equation and solve for the unknown pressure