Final answer:
G vs T can be plotted either as a straight line or a curve, depending on the relationship between Gibbs free energy and temperature. Line graphs are typically suited for continuous relationships, unlike bar graphs which compare categorical data.
Step-by-step explanation:
The plot of G (Gibbs free energy) versus T (temperature) can be represented in different ways depending on the nature of the relationship between these two variables. When the relationship between G and T is linear, which implies a constant change in G with respect to T, the plot will be a straight line, hence G vs T can be plotted as a straight line as option b) suggests. However, if the relationship is not linear, the plot of G versus T will result in a curve, indicating a variable change of G with respect to T, which aligns with option c) that G vs T can be plotted as a curve. Option d) is incorrect as G vs T is not limited to only being represented by a bar graph. Bar graphs are generally used to compare categorical data, as per Figure A7 and Figure A8, which is not typically how we represent a continuous relationship like that of G vs T. Line graphs are more appropriate for displaying continuous data and showing how one variable changes in response to another variable, as they effectively represent the relationship between two variables measured on the horizontal and vertical axes.