Vapour Pressure Calculator — calculate vapour pressure using standard chemistry formulas. Worked example with units.
Ideal Gas Law: PV = nRT, where R = 8.314 J/(mol·K) = 0.08206 L·atm/(mol·K)
Boyle's Law (constant T, n): P₁V₁ = P₂V₂
Charles's Law (constant P, n): V₁/T₁ = V₂/T₂ (T in Kelvin)
Gay-Lussac's Law (constant V, n): P₁/T₁ = P₂/T₂
Combined Gas Law: P₁V₁/T₁ = P₂V₂/T₂
van der Waals: (P + a(n/V)²)(V − nb) = nRT