According to Dalton’s Law, the [[Pressure|pressure]] of a [[Mixtures|mixture]] is equal to the sum of partial pressures of the mixture components. The partial pressure is the pressure exerted by a component at the same [[Temperature|temperature]] and [[Volume|volume]] as the mixture. $P=\sum P_i$ Partial pressures are directly related to the mole fraction of the component. $P_i=y_iP$