Scientists were able to isolate a relatively pure sample of selenium in 1817, the same year they first discovered the...
GMAT Expression of Ideas : (Expression) Questions
Scientists were able to isolate a relatively pure sample of selenium in 1817, the same year they first discovered the element's existence. ______ the isolation process took longer for molybdenum, which was isolated in its pure form three years after scientists first discovered it.
Which choice completes the text with the most logical transition?
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| Scientists were able to isolate a relatively pure sample of selenium in 1817, the same year they first discovered the element's existence. |
|
| [MISSING TRANSITION] |
|
| the isolation process took longer for molybdenum, which was isolated in its pure form three years after scientists first discovered it. |
|
Part B: Passage Architecture & Core Elements
Main Point: Different elements had different timelines between discovery and successful isolation.
Argument Flow: The passage contrasts the timing patterns of two elements - selenium was quickly isolated in its discovery year, while molybdenum required a longer three-year process between discovery and isolation.
Step 2: Interpret the Question Precisely
This is a fill-in-the-blank question asking us to choose the best logical connector. The answer must create the right relationship between what comes before and after the blank.
Step 3: Prethink the Answer
- The transition must connect the selenium information (quick isolation) with the molybdenum information (slower isolation)
- Since selenium was isolated the same year it was discovered, but molybdenum took 3 years longer, we need a word that shows contrast or difference
- The logical relationship is: selenium was fast vs. molybdenum was slow
- Perfectly signals the difference between selenium's quick isolation and molybdenum's longer process
- Matches our prethinking need for a contrasting transition
- Creates logical flow: fast selenium vs. slower molybdenum
- Indicates a result or conclusion following from the previous statement
- The molybdenum information doesn't result from the selenium information - they're separate facts about different elements
- Indicates the two situations are alike
- But selenium and molybdenum had opposite timing patterns (same year vs. 3-year gap)
- Introduces an example supporting a previous general statement
- But there's no general statement about element isolation timing that molybdenum would exemplify