The fractional distillation of a mixture of two compounds re

The fractional distillation of a mixture of two compounds resulted in the following distillation curve. A list of possible compounds with their bp\'s is also shown. Distillation Curve 110 100 90 9 80 E 70 60 50 compound boilin acetone methanol hexane 2-methyl-2 int (bp) ( C) 56 65 69 82 98 0 20 40 60 80100 120 ol ane Volume (drops) toluene 1-butanol What is the bp of the lower-boiling compound? What is the ratio of the amounts of higher-boiling to lower-boiling compounds (amt higher:amt lower - 1:1, 1:2, or 2:1)? What is the higher-boiling compound?

Solution

This question is graph based on fraction distillation of mixture of two compounds, So

Part 1:

As we can see from the graph, at 65 °C, the curve gets a saturation point, ie most of volume of gets ditilled at this temperature. Therefore, it is the lower boiling point of the compound, and this boiling point corresponds to methanol.

Part 2:

amount of lower boiling compound = 60 drops ( ie from 0 to 60 on x - axis or volume axis).

Amount of higher boiling compound = 30 drops (ie from 70 - 100 on x - axis or volume axis.)

So, amount of higher bp : amount of lower bp = 30 : 60

amount of higher bp : amount of lower bp = 1 : 2

Part 3: The higher boiling point is 98°C (as it can be seen from the graph) which corresponds to heptane in the table.