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Counting Replacement Sites in Carbon Models 4 questions
Counting Replacement Sites in Carbon Models
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A molecular display shows two C5H12 models. In both, carbon forms four bonds and hydrogen forms one. The display can replace one H with Cl. It counts different connections between atoms and ignores any differences that depend only on viewing orientation.
| Model | Carbon-to-carbon connections |
|---|---|
| P | A–B, B–C, C–D, D–E |
| Q | A–B, A–C, A–D, A–E |
Question 1
Which carbon in model Q has no hydrogen attached?
- A
- B
- C
- E
Question 2
Check the 12 hydrogen atoms in P by counting how many attach to its two end carbons and to its three inside carbons.
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In P, flipping the chain end for end interchanges A with E and B with D. In Q, rotating the model can interchange any of the four outer carbons with any other outer carbon.
Question 3
Compare how many different atom connections the one-H replacement can make in P and Q. Identify the different positions in P.
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Question 4
Draw a structure for model P in which Cl replaces one H attached to an inside carbon. Show the five carbon atoms and the bond to Cl. You may omit the other H atoms.
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