While researching a topic, a student has taken the following notes:Platinum is a rare and expensive metal.It is used as...
GMAT Expression of Ideas : (Expression) Questions
While researching a topic, a student has taken the following notes:
- Platinum is a rare and expensive metal.
- It is used as a catalyst for chemical reactions.
- Platinum catalysts typically require a large amount of platinum to be effective.
- Researcher Jianbo Tang and his colleagues created a platinum catalyst that combines platinum with liquid gallium.
- Their catalyst was highly effective and required only trace amounts of platinum (\(0.0001\%\) of the atoms in the mixture).
The student wants to explain an advantage of the new platinum catalyst developed by Jianbo Tang and his colleagues. Which choice most effectively uses relevant information from the notes to accomplish this goal?
Researcher Jianbo Tang and his colleagues created a platinum catalyst that combines platinum, a rare and expensive metal, with liquid gallium.
Like other platinum catalysts, the new platinum catalyst requires a particular amount of the metal to be effective.
Platinum is a rare and expensive metal that is used as a catalyst for chemical reactions; however, platinum catalysts typically require a large amount of platinum to be effective.
While still highly effective, the new platinum catalyst requires far less of the rare and expensive metal than do other platinum catalysts.
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "Platinum is a rare and expensive metal." |
|
| "It is used as a catalyst for chemical reactions." |
|
| "Platinum catalysts typically require a large amount of platinum to be effective." |
|
| "Researcher Jianbo Tang and his colleagues created a platinum catalyst that combines platinum with liquid gallium." |
|
| "Their catalyst was highly effective and required only trace amounts of platinum (0.0001% of the atoms in the mixture)." |
|
Part B: Provide Passage Architecture & Core Elements
Main Point: Researchers developed a new platinum catalyst that maintains high effectiveness while using dramatically less platinum than traditional catalysts.
Argument Flow: The notes establish platinum as valuable but limited by high usage requirements in catalysts, then present Tang's team's breakthrough that solves this problem by achieving effectiveness with minimal platinum content.
Step 2: Interpret the Question Precisely
What's being asked? We need to explain an advantage of Tang's new platinum catalyst.
What type of answer do we need? A statement that clearly shows how the new catalyst is better than traditional ones.
Any limiting keywords? The word "advantage" is key—we need to show what makes this catalyst superior, not just describe what it is.
Step 3: Prethink the Answer
- From our analysis, the main advantage is clear: this new catalyst solves the cost/efficiency problem
- Traditional catalysts need "a large amount of platinum" (which is "rare and expensive")
- Tang's catalyst is "highly effective" while using "only trace amounts of platinum"
- The right answer should:
- Reference that the catalyst is still highly effective
- Emphasize that it uses much less platinum than traditional catalysts
- Connect this to the economic benefit (since platinum is rare and expensive)
Researcher Jianbo Tang and his colleagues created a platinum catalyst that combines platinum, a rare and expensive metal, with liquid gallium.
- Simply describes what the researchers created without mentioning any advantage
- Mentions platinum is "rare and expensive" but doesn't explain how the new catalyst addresses this issue
Like other platinum catalysts, the new platinum catalyst requires a particular amount of the metal to be effective.
- Says the new catalyst requires "a particular amount" of platinum, which is vague
- Uses phrase "like other platinum catalysts," suggesting similarity rather than advantage
Platinum is a rare and expensive metal that is used as a catalyst for chemical reactions; however, platinum catalysts typically require a large amount of platinum to be effective.
- Only provides background information about platinum and traditional catalysts
- Doesn't mention Tang's new catalyst at all
While still highly effective, the new platinum catalyst requires far less of the rare and expensive metal than do other platinum catalysts.
- Clearly states the catalyst is "highly effective" (maintains performance)
- Emphasizes it "requires far less of the rare and expensive metal" (economic advantage)
- Uses "while still" to show the catalyst maintains effectiveness despite using less platinum