Calculate the vapor pressure of propanol (b.p. 97.0 ∘C97.0 ∘C) at the gas chromatography column temperature of 95.0 ∘C95.0 ∘C using the form of the Clausius–Clapeyron equation shown   ln(?1?2)=−(Δ?vap?)(1?1−1?2)ln(P1P2)=−(ΔHvapR)(1T1−1T2)   where ?R is the ideal gas constant, Δ?vapΔHvap is the enthalpy of vaporization, ?1T1 and ?2T2 are two different temperatures, and ?1P1 and ?2P2 are the vapor pressures at the respective temperatures. The enthalpy of vaporization can be estimated using Trouton's rule, Δ?∘vap=(88 J·mol−1⋅K−1)×?bp.ΔHvap∘=(88 J·mol−1⋅K−1)×Tbp. ?=P=   TorrTorr Calculate the vapor pressure of pentane (b.p. 36.0 ∘C36.0 ∘C) at the same column temperature. ?=P=   TorrTorr For compounds of the same chemical class, what is the relationship between vapor pressure of a compound and retention in gas chromatography? As the vapor pressure decreases, retention time decreases. As the vapor pressure increases, retention time increases. As the vapor pressure increases, retention time decreases. There is no relationship between vapor pressure and retention.

Only Part i, it should say “normal boiling point”

The Gibbs energy of mixing of a regular solution of components A and B is given by Greal = nRT (x Inx +x Inx +ẞXX), where X and X are mix A B B A B the mole fractions of the two components and ẞ is a dimensionless parameter quantifying deviations from ideal behaviour in terms of the relative strength of A-B interactions compared to A-A and B-B interactions. (i) Use a spreadsheet to calculate A Greal/nRT for XA = 0.01, 0.125, mix 0.25, 0.5, 0.75, 0.875 and 0.99 for ẞ= 0, 1 and 3. Report your calculations in a table and, using a labelled plot, determine the numbers of minima in A Greal/nRT as a function of composition and ẞ. mix [3 (ii) For each value of ẞ, predict the number of liquid phases which you would expect for the mixture. Justify your answer in terms of A-B interactions. [

A student performed the fractional distillation of a cyclohexane/toluene mixture. The refractive index of the distillate was measured at 1.4301 with an ambient temperature of 22.0oC. What is the mole percentage of cyclohexane (to 3 sf)?