In preparing graphs to display information about vapor-liquid equilibrium for binary systems, which of the following approaches should you hesitate to use?

Question

A. Use dashed or solid lines/curves for model results.
B. Use symbols for discrete experimental data.
C. Use different colored solid lines/curves for different models.
D. Include the variable being held constant (temperature or pressure) on the graph or in caption.
E. All of the approaches are appropriate to use.

Answer 1

A. Incorrect. This is an approach to use. Showing models as solid or dashed lines/curves is appropriate since you can control the number of points in the domain to make the line or curve smooth.
B. Incorrect. This is an approach to use. Discrete data should be shown as symbols. Occasionally, data can be presented with dashed/solid curves as a “guide for the eye” as long as it is stated as such in the caption and there is no model comparison.
C. Correct. You should hesitate to use this approach. Often items are copied, leaving black and white reproductions. Thus, it becomes difficult or impossible to tell the differences between two models. It is better to discriminate between them with dashed or dotted curves.
D. Incorrect. This is an approach to use. You need to specify the temperature or pressure that is fixed when presenting the data in the figure.
E. Incorrect. At least one approach is not good practice.