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Drawing Two Places for Oxygen in a Chain 4 questions
Drawing Two Places for Oxygen in a Chain
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A molecule display shows three models with the same atom counts. It can erase one bond at a time and count the carbon atoms on the two separated pieces. This is a bond-model exercise. The first setting erases one bond between C and O. In each formula a dash shows a single bond, and parentheses show a branch attached to the preceding carbon.
| Model | Condensed formula |
|---|---|
| P | CH3–CH2–CH2–O–H |
| Q | CH3–O–CH2–CH3 |
| R | CH3–CH(O–H)–CH3 |
Question 1
For P and R, give the carbon count in each of the two pieces after erasing the C–O bond. Explain why this result cannot distinguish the two models.
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Question 2
Which model can yield a one-carbon piece and a two-carbon piece when the first setting erases a single C–O bond?
- P only
- Q only
- R only
- P and R only
The first setting leaves a zero-carbon piece and a three-carbon piece from an unknown that matches one of the three models. On a fresh copy, a second setting erases one C–C bond next to the carbon bonded to oxygen. It gives a one-carbon piece that still holds O and a two-carbon piece without O.
Question 3
Identify the unknown. Explain what each of the two settings rules out.
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Question 4
Draw the carbon skeleton of R, including its attached O. Mark one bond the second setting could erase and give the carbon count of the piece that still contains O.
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