Ordinary soap bubbles usually exist for a minute or less before popping due to either a rupture forced by gravity-induced...
GMAT Craft and Structure : (Structure) Questions
Ordinary soap bubbles usually exist for a minute or less before popping due to either a rupture forced by gravity-induced drainage or the evaporation of the liquid from which the bubble is composed. But physicist Aymeric Roux and colleagues discovered ways to mitigate these factors, resulting in bubbles that can last for a year or more. For example, glycerol tends to adhere to water molecules, so a bubble with a shell that contains both water and glycerol is able to draw additional water molecules from the surrounding air and thereby compensate for evaporation.
Which choice best states the purpose of the underlined portion in the text as a whole?
It describes the effects of a process devised by researchers that increases the longevity of an object discussed in the text.
It details the circumstances that prompted the research discussed in the text.
It presents a reason why the phenomenon discussed in the text that the researchers wanted to avoid will inevitably occur.
It mentions a method discussed in the text that researchers intend to test in future experiments.
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "Ordinary soap bubbles usually exist for a minute or less before popping due to either a rupture forced by gravity-induced drainage or the evaporation of the liquid from which the bubble is composed." |
|
| "But physicist Aymeric Roux and colleagues discovered ways to mitigate these factors, resulting in bubbles that can last for a year or more." |
|
| "For example, glycerol tends to adhere to water molecules, so a bubble with a shell that contains both water and glycerol is able to draw additional water molecules from the surrounding air and thereby compensate for evaporation." |
|
Part B: Provide Passage Architecture & Core Elements
Main Point: Researchers have discovered methods to dramatically extend soap bubble lifespans from minutes to over a year.
Argument Flow: The passage first establishes the problem (bubbles pop quickly due to known causes), then presents the solution (researchers found ways to counteract these factors for much longer-lasting bubbles), and finally provides a concrete example of how one method works by using glycerol to compensate for evaporation.
Step 2: Interpret the Question Precisely
What's being asked? The purpose or function of the underlined portion (the final sentence about glycerol) within the context of the entire text.
What type of answer do we need? A description of what role this sentence plays in the overall passage structure.
Any limiting keywords? None specified.
Step 3: Prethink the Answer
- The underlined portion (the glycerol sentence) serves as a concrete example that explains exactly how the researchers' solution works
- It shows us the mechanism behind their breakthrough - specifically how they address the evaporation problem that normally causes bubbles to pop quickly
It describes the effects of a process devised by researchers that increases the longevity of an object discussed in the text.
✓ Correct
- Accurately describes the sentence as explaining "effects of a process devised by researchers" - the glycerol method is indeed a researcher-created process
- Correctly identifies that this process "increases the longevity" of bubbles
It details the circumstances that prompted the research discussed in the text.
✗ Incorrect
- Claims the sentence describes "circumstances that prompted the research" but the glycerol example doesn't explain why researchers started this work - it explains how their solution works
It presents a reason why the phenomenon discussed in the text that the researchers wanted to avoid will inevitably occur.
✗ Incorrect
- States the sentence presents why the problematic phenomenon "will inevitably occur" but this is backwards - the glycerol example shows how to prevent/compensate for evaporation, not why it's inevitable
It mentions a method discussed in the text that researchers intend to test in future experiments.
✗ Incorrect
- Suggests the sentence mentions "a method...researchers intend to test in future experiments" but the glycerol method is presented as something that already works, not a future experiment