Heptane and octane form an ideal solution. At `373 K`, the vapour pressure of the two liquids are `105.0` kPa and `46.0` kPa, respectively. What will be the vapour pressure, of the mixture of `25 g` of heptane and `35 g ` of octane ?

Explanation

`P_(M) = P'_("Heptane") + P'_("Ocatne") `
`=P_("Heptane")^(@)xxn/(n+N)+P_("Ocatane")^(@)xxN/(n+N)`
(`mol` wt. of `C_(7)H_(16) = 100, "mol"`. Wt. of `C_(8)H_(18) = 114`)
`= 105.2 xx (25//100)/((25)/(100)+(35)/(114)) + 46.8 xx (35//114)/((25)/(100)+(35)/(114))`
`= 73.08 kPa`