Question

1- Acetone (1) and Methanol (2) form an azeotrope boiling at 55.7^oC at 1 atm pressure, with a composition x₁ = 0.80. Calculate the van Laar Coefficients for the system.

2- Perry (Table 13-1) quotes the following x,y,T data for Acetone (1) and Methanol (2) at 101.3 kPa total pressure. Estimate the van Laar constants A₁₂ & A₂₁.

T/oC	64.65	61.78	59.60	58.14	56.96	56.22	55.78	55.41	55.29	55.37	55.54	55.92	56.21
x1	0	0.091	0.190	0.288	0.401	0.501	0.579	0.687	0.756	0.840	0.895	0.954	1.000
y1	0	0.177	0.312	0.412	0.505	0.578	0.631	0.707	0.760	0.829	0.880	0.946	1.000

3- The following data for the system Acetone(1) Methanol(2) at 55^oC are taken from the Landolt-Börnstein tables, Vol IV/3 Table 306. Use them to calculate the van Laar constants A₁₂ and A₂₁.

x1	0.0287	0.0570	0.0644	0.0858	0.1046	0.7752	0.7922	0.9080	0.9088	0.9197	0.9448
P/bar	0.7228	0.7527	0.7593	0.7752	0.7895	1.0099	1.0105	0.9987	1.0003	1.0005	0.9979

4- A liquid containing 70% molar acetone and 30% methanol is to be heated to 100^oC without boiling.   Calculate the minimum pressure needed.

5- Calculate the bubble point at 1 atm pressure and the vapour composition in equilibrium with a liquid containing 25% molar acetone and 75% molar methanol.

6- Calculate the dewpoint at 1 atm pressure and the equilibrium liquid composition of a vapour containing 25% acetone (1) and 75% methanol (2).

7- A liquid containing 30% molar acetone (1) and 70% methanol (2) is heated to 70^oC at 2 atm pressure. The pressure is reduced to 1.5 atm, supplying heat to maintain a temperature of 70^oC. Calculate the fraction evaporated (molar basis) and the composition of the liquid and vapour streams.

Answer 1