Logical reasoning PrepTest 156 · Section 4 · Question 1

Although it mentions costs, this answer choice doesn't weaken Peterson's argument. Sure, the cost of organic solvents is only one of many expenses involved in chemical production. But if ionic liquids cost more than organic solvents, it would still be cheaper to go with organic solvents, all other costs being equal. If this answer choice said that ionic liquids reduced these other costs, it might weaken Peterson's argument. But, alas, this answer choice doesn't say that.

Moreover, this answer choice discusses the costs associated with the "production of chemicals." That isn't necessarily the same thing as the "chemical processes" that the passage discusses. So, there's a chance this answer choice isn't even about the same topic as Peterson's argument.

This answer choice doesn't address the cost of ionic liquids, so it can be a quick elimination. Besides, the existence of new methods to remove unwanted by-products would weaken Montoya's argument, not Peterson's. According to Montoya, one of the benefits of ionic liquids is that they produce fewer unwanted by-products. If new methods make it easy to remove unwanted by-products, then this "benefit" of ionic liquids doesn't seem so beneficial.

This answer choice doesn't address the cost of ionic liquids, so we can cross it off immediately. Still, some test-takers are tempted by this option, as it appears to strengthen Montoya's argument. After all, Montoya argues that ionic liquids can increase the rate at which chemical reactions occur. If the chemical industry has historically adopted technologies that do that, this answer choice shows that chemical companies value this characteristic and may want to adopt ionic liquids.

But while this answer choice may strengthen Montoya's argument, it doesn't weaken Peterson's. Even if the chemical industry values technologies that increase the rate at which chemical reactions occur, it still may not be practical to adopt ionic liquids, given the liquid's high cost. Chemical companies may have historically adopted only the cheap new technologies that increase the rate at which chemical reactions occur. In other words, because this answer choice doesn't show why the cost of ionic liquids isn't a dealbreaker, it doesn't weaken Peterson's argument.

This is the only answer that addresses the high cost of ionic liquids. Unsurprisingly, it is correct.

As expected, this answer choice shows that chemical companies can recoup the high cost of ionic liquids. If ionic liquids can be reused many times and organic solvents can only be used once, ionic liquids may be less expensive than organic solvents in the long run. Chemical companies would need to pay for organic solvents for every chemical process but would only need to pay for ionic liquids for the first process. Therefore, this answer choice shows why the high cost of ionic liquids isn't a big deal, weakening Peterson's argument.

Many test-takers find this answer choice enticing because it seemingly strengthens Montoya's argument. Montoya argues that ionic liquids produce less air pollution. So, if chemical companies will use the more "environmentally friendly" process even if it costs more, wouldn't this vindicate Montoya's argument?

Not quite. There are a few reasons why this answer choice doesn't weaken Peterson's argument. First, we don't know that ionic liquids are "more environmentally friendly" than organic solvents. We know ionic liquids produce less air pollution, but they can still damage the environment in many other ways. It's possible that ionic liquids are, on balance, less environmentally friendly than organic solvents.

Second, this answer choice uses the weak, wishy-washy language ("sometimes") we don't like on Weaken questions. Sure, companies may sometimes use more environmentally friendly processes. But maybe that happens with, like, 1% of the processes companies use. That's enough to say that companies "sometimes" use more costly but environmentally friendly processes for PR. But it would still mean that companies almost always prefer the cheaper, dirtier option.

Finally, a close reading will show that this answer choice doesn't even address Peterson's argument. Peterson's argument is about chemical companies, while this answer choice is about companies in general. Perhaps chemical companies never use more environmentally friendly products. Plus, this answer choice says that companies may use a process that is "slightly more expensive." However, Peterson argues that ionic liquids cost "many times as much as organic solvents." So, this answer choice doesn't address the specific companies Peterson brings up, and it doesn't address the much more expensive processes that Peterson brings up.