Question

9. Which statement accurately describes the graph?
A. Reaction 2 occurs faster than Reaction 3 because Reaction 2 requires more energy than Reaction 3.
B. Product B contains more energy at the end of the reaction than reactant A has at the beginning of the
reaction.
C. Reactant A contains more energy at the beginning of the reaction than product C has at the end of the
reaction.
D. The data plotted for Reaction 2 and Reaction 3 indicate a difference in the activation energy of these
reactions.

Answer 1

Answer:

D

Explanation:

Each reaction starts at 0J (i.e. no energy). So, you can eliminate C. and B. simply by comparing the start point (A) to those end points.

Product B does not contain more energy than reactant A because the line falls below the axis (falls below zero). (You can apply this same logic for question C)

A. is incorrect because all the reactions appear to be occurring on the same time scale.

D. is the best answer because activation energy is best identifiable difference between these three reactions. The 'hump' in the graph represents the activation energy. The higher the hump, the higher the energy.

Let me know if anything sounds wrong! Cheers.