Heptane (C7H16) and octane (C8H18) are constitutents of gasoline. At 80 degree celsius, the vapor pressure of heptane is 428mmHg and the vapor pressure of octane is 175mmHg. What Xheptane in a mixture of heptane and octane that has a vapor pressure of 305mmHg and 80 degree celsius?

Question

Chemistry

Hadley

20 July, 18:26

Heptane (C7H16) and octane (C8H18) are constitutents of gasoline. At 80 degree celsius, the vapor pressure of heptane is 428mmHg and the vapor pressure of octane is 175mmHg. What Xheptane in a mixture of heptane and octane that has a vapor pressure of 305mmHg and 80 degree celsius?

+5

Answers (1)

Know the Answer?

Alvaro · Answer 1

Looking at this equation P = (pa*pb) / (pa + (pb-pa)) ya where pa=vap press a and ya = vap composition a and P = total pressure, it relates vapor pressure mixture to vapor composition. This is derived using the combination of Dalton's and Raoult's laws.