Question 74·Easy·Command of Evidence
A chemistry class tested several catalysts for the decomposition of hydrogen peroxide. They measured the volume of oxygen gas collected after 5 minutes. Their results are shown in the graph.
Although potassium iodide produced a large amount of oxygen, it produced less oxygen than that of _____.
Which choice most effectively uses data from the graph to complete the comparison?
For graph-based comparison questions, translate the sentence into a clear math idea (here, “potassium iodide is less than the blank”). Then read the relevant bar’s height and choose the one option whose bar is higher. Don’t overthink the science context—use the visual evidence.
Hints
Focus on one bar first
Start by finding the bar for potassium iodide and estimating its height on the y-axis.
Compare heights
Look for any bar that is higher than the potassium iodide bar.
Match the comparison word
The blank must be filled with something that produced more oxygen than potassium iodide.
Step-by-step Explanation
Locate potassium iodide on the graph
Find the bar labeled Potassium iodide and note its oxygen volume after 5 minutes.
Identify any bar higher than potassium iodide
Compare the height of the potassium iodide bar to the other bars and look for one that is clearly taller.
Choose the catalyst with the higher oxygen volume
Only Manganese dioxide has a higher oxygen volume than potassium iodide, so it correctly completes the comparison.