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MDCAT
Chemistry
2022

Chemistry · Hydrocarbons

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Question

What is the name of CH3CH2CH=CHCH2CH=CHCH3 ?

Options
  • A

    2,3-octadiene

  • B

    2,4-octadiene

  • C

    2,5-octadiene

  • D

    2,5-octadyne

Explanation

The parent chain is 8 carbons long so it is -octa and diene because of the 2 double bonds. Also the position of these double bonds is correctly indicated in option C.

This option is incorrect.

2,3-octadiene: Incorrect because the double bonds are not located between carbons 2 and 3.

Incorrect

The compound has eight carbon atoms, so the base name is "octa-".

* It has two double bonds (=), so it's a "diene".

* The double bonds are located between carbons 2 and 3, and between carbons 4 and 5. Therefore, the correct name includes 2,4-

* Thus, the correct answer is 2,5-octadiene

The compound has eight carbon atoms, so the base name is "octa-".

* It has two double bonds (=), so it's a "diene".

* The double bonds are located between carbons 2 and 3, and between carbons 5 and 6. Therefore, the correct name includes 2,4-

* Thus, the correct answer is 2,4-octadiene

2,5-octadyne: Incorrect because it suggests the presence of triple bonds (-yne), not double bonds (-ene).

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Tagged under Chemistry · Hydrocarbons · 2022