TBR O-chem chapter 4: question contradictions

[shnarf9892]

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Could someone shed some light on this? In the review questions for TBR Ochem chapter 4, #25 (page 294 in the 2013 edition) reads as follows with the correct answer choice in bold:

Terpenes have all of the following properties EXCEPT:
A. High volatility
B. distinct odor
C. fluidity at room temperature
D. high water solubility

However, when I get to the practice exam, #50 (page 309) completely contradicts the previous question. Again, the correct answer is in bold.

All of the following are physical properties of a terpene EXCEPT:
A. high lipid solubility
B. High boiling point
C. Low volatility
D. High specific rotation

In one question, they say terpenes are highly volatile, while in the other, it is stated that they have low volatility and a high boiling point, which I'm fairly certain is a contradiction. See my issue? I just want to learn the material as best as I can, but when I get contradictory information from my prep books, I get frustrated.

 

[AwayFromReality]

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[AwayFromReality]

Alright just looked up those two problems and their respective explanations in my TBR book. The two questions are definitely contradictory because one says terpenes have high volatility while the other says low volatility.

I didn't really like TBR's explanation for volatalities of Terpenes in question # 25. But I do agree with their explanation for question #50. Volatility is inversely related with boiling point so low volatility is the same thing as High boiling point. Since a question cannot have two correct answers B and C can be eliminated. A is always true since terpenes are hydrocarbons. That only leaves choice D.

 

[Cawolf]

I remember getting that question wrong also.

 

[whistle47]

yeah this is the most upsetting part of the mcat - there's a least incorrect answer instead of a correct answer. perhaps it will help you sleep at night if you think about the range of possible terpenes - isoprene is pretty volatile (bp 307 K) and obviously the big fat terpenes are not volatile.