Reading comp PrepTest 156 · Section 3 · Question 25

Passage

  Organic chemist Larry Koskan's inspiration arrived in the mid-1980s, when he read a report by marine biologists describing how oyster Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Paragraph 1

  • Paragraph note
    • Background on Koskan’s inspiration (discovery that oysters produce protein-based agents)

Paragraph 2

  • Paragraph note
    • Comparison of polyacrylates (used to decrease scale on water-treatment equipment) and oyster's polyaspartate (can also decrease scale, but is biodegradable)
  • Views, minor Meta-Structures, and the author’s attitude
    • Cause-and-effect relationships, according to the author:
      • Polyacrylate causes a decrease in damaging mineral-scale deposits on surfaces of water-treatment equipment (second sentence)
      • Polyaspartate causes a decrease in the formation of calcium carbonate, which causes a decrease in damaging mineral-scale deposits on surfaces of water-treatment equipment (third sentence)
    • Comparisons, according to the author:
      • Polyacrylate and polyaspartate have a similar chemical structure (fourth sentence)
      • Unlike polyacrylate, polyaspartate is made up of peptides, so it is biodegradable (last sentence)

Paragraph 3

  • Paragraph note
    • Problem with polyacrylates (prevalent in detergents and diapers but last forever in landfills)
  • Views, minor Meta-Structures, and the author’s attitude
    • Author's view:
      • Polyacrylates are inexpensive and versatile, so they are used extensively in laundry detergents and baby diapers, even though they last virtually forever in landfills (first through last sentences)
    • Author's attitude: "inexpensive and versatile" (first sentence); "ideal" (fourth sentence); "trouble" (last sentence); "last virtually forever" (last sentence); "vast quantities" (last sentence)

Paragraph 4

  • Paragraph note
    • Author on the industry's waning interest in polyaspartate (too expensive) and the success of Koskan's company (successful at eliminating scale in offshore oil equipment and keeping fertilizer in soil)
  • Views, minor Meta-Structures, and the author’s attitude
    • Comparison, according to the author:
      • While the consumer products and chemical industry's early enthusiasm for polyaspartate eventually waned as it proved too expensive, Koskan's company believed that polyaspartate could work in specialized applications (second through fifth sentences)
    • Author's view:
      • Polyaspartate has shown unmatched success at eliminating scale in offshore oil equipment and reducing groundwater pollution, and Koskan's company's continued success would revitalize an environmental chemical industry with a reputation for ineffectiveness and high cost (sixth and last sentences)
    • Author's attitude: "growing rapidly" (first sentence); "Unfortunately" (third sentence); "unparalleled success" (sixth sentence); "may yet help enliven an environmental chemistry sector saddled with a reputation for ineffectiveness and high cost" (last sentence)

Main Point: Although using polyaspartate as a more environmentally friendly alternative to polyacrylate has proven too expensive for many companies, Koskan's use of polyaspartate in specialized applications has shown tremendous success.

Meta-Structure?

Problem/Solution: This passage best fits the Problem/Solution Meta-Structure*. In such a passage, the author will describe an issue and one or more potential solutions. In this particular passage, the author presents the problem with the extensive use of polyacrylates. While they are cheap and versatile (and less environmentally damaging than some products), they pretty much last forever in landfills. The author presents polyaspartate as a possible solution — this chemical functions similarly to polyacrylates, but they're biodegradable and thus more environmentally friendly.

In a Problem/Solution passage, the main point is generally the author’s opinion on the solution. The author doesn't summarize their opinion in one or two sentences, so we had to compose our own summary: "Although using polyaspartate as a more environmentally friendly alternative to polyacrylate has proven too expensive for many companies, Koskan's use of polyaspartate in specialized applications has shown tremendous success."

*That said, a few other Meta-Structures could work for this passage. You could certainly call this an Innovative [Subject] or Importance of [Subject] passage, framing Koskan as the innovative/important figure. If you classified this passage as either of these Meta-Structures, you'd probably come to a similar understanding of the passage's main point and organization.

Comparison: The author compares and contrasts polyacrylate and polyaspartate several times in this passage, making the comparison the most prominent minor Meta-Structure. Expect a question or two about these. To avoid some fact-finding missions and save some time, you can commit a few similarities and differences to memory if this isn't too onerous:

  • Similarities: Similar chemical structure, both decrease scale
  • Differences: Polyaspartate is made up of peptides and not hydrocarbon, polyaspartate is biodegradable, polyacrylate is cheap

Last Thoughts?

The words "polyacrylate" and "polyaspartate" are long, very similar, and there's a good chance you're unfamiliar with both. We're going to have a bad time if we mix them up. So, let's devise a strategy to make sure we know which is which. Personally, we're just going to scan the end of the word to see if it ends with "-late" or "-tate." The one that ends with "-late" has been used to control scale and put in products like laundry detergent and baby diapers. It's also the one that Koskan wants to say "late(r)" to, replacing it with the more modern "-tate." The "-tate" one is also biodegradable ... like a po-tate-o? Whatever the mnemonic device you come up with, the questions will be much easier if we can remember which one is "polyacrylate" and which is "polyaspartate."

Question prompt

It can most reasonably Remaining source text redacted.
Why the credited answer is right

Credited answer: C

The notes below walk through why it fits the stem and how to eliminate the rest.

Strategy Overview

Consult your notes or passage to recall the author’s attitude about the topic in question, and find the answer that best reflects your understanding of the author’s opinion on that topic

Answer Anticipation

This question asks us to find the answer choice about leading chemical companies' failure to fully embrace polyaspartate as a replacement for polyacrylates that the author would most likely agree with. We can review our notes and what we highlighted/underlined to determine where the discussion of this topic takes place. Once we locate the relevant parts of the passage, we can review those to anticipate what the correct answer might say. Looking at our notes, we'll notice the author mentions chemical companies' "waning interest" in polyaspartate in the fourth paragraph. There, the author claims the industry lost interest in polyaspartate as a "replacement for polyacrylates" when they realized that polyaspartate costs four to five times more than polyacrylate (P4, S2-S4). So, the correct answer will likely say that the chemical companies' failure to fully embrace polyaspartate resulted from polyaspartate's high cost or something to that effect.

Answer choices

  1. A
    was a result of Remaining source text redacted.
    Why choice A is not credited

    Is this consistent with the author's claim that chemical companies didn't fully embrace polyaspartate due to polyaspartate's high cost?

    Nope, so we can eliminate (A). When reviewing the last paragraph, we didn't encounter anything about polyaspartate's "potentially harmful consequences to human health." So, we don't have any reason to believe that the author would agree with this statement.

  2. B
    was not primarily a Remaining source text redacted.
    Why choice B is not credited

    Is this consistent with the author's claim that chemical companies didn't fully embrace polyaspartate due to polyaspartate's high cost?

    Nope. In fact, this is entirely inconsistent with the author's claim that chemical companies didn't fully embrace polyaspartate due to polyaspartate's high cost. We don't have any reason to believe that chemical companies didn't fully embrace polyaspartate for reasons other than cost, so we can cross off (B).

  3. C
    was not due to Remaining source text redacted.
    Why choice C matches the stem

    Is this consistent with the author's claim that chemical companies didn't fully embrace polyaspartate due to polyaspartate's high cost?

    Yep. If chemical companies lost interest in polyaspartate due to its cost, then it's definitely true that chemical companies' failure to fully embrace polyaspartate was not "due to a widely accepted belief that polyaspartate is ineffectual." Based on anticipation, we can select (C) and move on.

    But if you wanted to be safe, we could again check the fourth paragraph. There, we'll see that the consensus among chemical companies was "that polyaspartate was the most suitable replacement for polyacrylates" (P4, S2). So, the chemical companies definitely didn't think that polyaspartate was ineffective. Therefore, we can confidently select (C) and advance to the following question.

  4. D
    was a result of Remaining source text redacted.
    Why choice D is not credited

    Is this consistent with the author's claim that chemical companies didn't fully embrace polyaspartate due to polyaspartate's high cost?

    Negative, so we can eliminate (D). When reviewing the last paragraph, we didn't encounter anything about the "relative scarcity of the raw material from which polyaspartate is made." Polyaspartate is expensive, but we don't know if it's expensive because the raw materials are scarce.

  5. E
    was due to the Remaining source text redacted.
    Why choice E is not credited

    Is this consistent with the author's claim that chemical companies didn't fully embrace polyaspartate due to polyaspartate's high cost?

    No, so we can eliminate (E). When reviewing the last paragraph, we didn't encounter anything about whether consumers wouldn't trust products containing polyaspartate. So, we don't have any reason to believe that the author would agree with this statement.

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 8%
  2. B 17%
  3. C Credited 59%
  4. D 12%
  5. E 4%

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