Question

sorry the graph was cut into two pieces, both parts of it are posted, please show all work and answer all parts. Thank you.

5/25/19, 8 21 PM 370 365 360 355 350 1 0.1 0.9 0.8 0.2 0.6 0.7 0.3 0 0.4 0.5 Mole Fraction of Benzene Specify the boiling points of benzene and toluene. a. Benzere'r b.p ir 80.0-80.2 Toluendr b.p is 110°C Page 4 of 5 b. A mixture of benzene and toluene begins to boil at 370 K. What is the mole fraction of each component at this boiling point. the nde fadtion Beatre at the li ine CN at a70kr and .325 that mo th mode factin oftthe tolvne mur aon 0.625. Beazereso.375tdvere o.625 c. For a mixture of 50% benzene and 509% totuene, what is the mole fraction of each component in the vapor when that liquid begins to boil? d. What is the new boiling point of the liquid formed by condensation of the vapor from c.? e. What is the minimum number of theoretical plates needed to isolate benzene of at least 95% purity from a mixture of 10.00 g benzene (MW 78.11 g/mol) and 39.32 g toluene (92.14 g/mol). Show mathematical work below. Draw the theoretical plates directly on the graph above. Tempe 15 Below is a composition diagram for a mixture of benzene and toluene at 760 Tor. Use this graph to 6. answer the questions that follow Composition Diagram For a Binary Mixture of Benzene and Toluene 400 395 390 385 380 375 rature (K)

Answer 1

(a) two graphs cut at temperature axis at 383K and 353K i.e. mole fraction of benezen as 0 and 1. (Correspondening to toluene and benzene).

boiling point of toluene = 383K = 110℃

Boiling point of benzene = 353K = 80℃

(b)

Horizontal line at temperature equals to 370K, cut the curve at mole fraction of benzene as 0.375 . Mole fraction of toluene would be 0.625.

(c)

When the solution has 50% benzene and toluene each, it would boil at 365K. The horizontal line at 365K would cut the vapor curve at 0.75 mole fraction.

Mole fraction of benzene in vapor phase = 0.75

Mole fraction of toluene in vapor phase = 1-0.75 = 0.25

(d)

0.75 composition liquid cuts the lower curve at temperature, 359K close to 360K. The value can be calculated using proper scale only.

Boiling point = 359 or 360 K

(e)

Mole fraction of benzene = moles of benzene/total number of moles

= 10.00g/78.11g/mol ÷(10.00/78.11 + 39.32/92.14)

= 0.23

Number of theoretical plates can be calculated by drawing the graph as shown in the picture below. Answer can be calculated with proper scale. I have drawn the picture for reference.

Approximate value comes out to be 4 or 5.

Vapoi iquid 0.23 benzene.