The majority of plastics today wind up in landfills or are, at best, recycled into materials that have a very...
GMAT Craft and Structure : (Structure) Questions
The majority of plastics today wind up in landfills or are, at best, recycled into materials that have a very limited range of applications. To address this problem, chemist Guoliang Liu and colleagues designed a reactor that melts polyethylene and polypropylene—two widely used plastics—into a wax. The wax can then be transformed into a surfactant (a chemical compound usable as a detergent). With this promising new method, plastic waste could be turned into a range of useful cleaning products.
Which choice best states the function of the underlined portion of the text?
It clarifies the meaning of a scientific term.
It describes an environmental concern.
It explains the significance of a scientific discovery.
It identifies a result that confused the team.
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "The majority of plastics today wind up in landfills or are, at best, recycled into materials that have a very limited range of applications." |
|
| "To address this problem, chemist Guoliang Liu and colleagues designed a reactor that melts polyethylene and polypropylene—two widely used plastics—into a wax." |
|
| "The wax can then be transformed into a surfactant (a chemical compound usable as a detergent)." |
|
| "With this promising new method, plastic waste could be turned into a range of useful cleaning products." |
|
Part B: Provide Passage Architecture and Core Elements
Visual Structure Map:
PROBLEM: Plastics go to landfills or limited recycling
SOLUTION: Liu reactor converts plastics to wax to surfactant to cleaning products
SIGNIFICANCE: Promising method for useful products
Main Point: Scientists have developed a new method to convert plastic waste into useful cleaning products by transforming it first into wax, then into surfactants.
Argument Flow: The passage first establishes the problem with current plastic disposal methods, then introduces Liu reactor as a solution that transforms specific plastics into wax, which can become surfactants for cleaning products, concluding with the broader potential of this approach.
Step 2: Interpret the Question Precisely
What's being asked? The function of the specific underlined portion about chemical compound usable as a detergent
What type of answer do we need? The purpose or role this phrase serves in the text
Any limiting keywords? We need to focus only on that specific phrase, not the whole sentence
Step 3: Prethink the Answer
- The underlined portion comes immediately after the word surfactant
- Since surfactant is a scientific/technical term that many readers might not know, this parenthetical phrase is explaining what a surfactant actually is
- It's giving us the definition in simpler, more familiar terms
- The right answer should tell us that this phrase is defining or clarifying a technical term for the reader
It clarifies the meaning of a scientific term.
✓ Correct
- This perfectly captures what the underlined portion does - it takes the scientific term surfactant and explains what it means in everyday language
- The phrase literally defines surfactant as a chemical compound usable as a detergent, which is exactly what clarifying a scientific term looks like
It describes an environmental concern.
✗ Incorrect
- The environmental concern was already described in the opening sentence about plastics in landfills
- This parenthetical phrase isn't describing any problem - it's just defining a term
It explains the significance of a scientific discovery.
✗ Incorrect
- The significance of the discovery is explained in the final sentence about turning waste into useful products
- This phrase isn't explaining importance - it's just telling us what a surfactant is
- Students might think any explanation in a science passage is about significance, but definitions serve a different purpose
It identifies a result that confused the team.
✗ Incorrect
- Nothing in the passage suggests the team was confused about anything
- The parenthetical phrase is straightforward clarification, not addressing confusion