Photo AI
Which of the following is an isomer of pentan-3-ol? A - Scottish Highers Chemistry - Question 8 - 2017
Question 8
Which of the following is an isomer of pentan-3-ol? A. CH₃CH(CH₂)CH₂CH₃ B. CH₃CH(CHCH₂)CH₂OH C. CH₃CH(CHCH(OH)CH₃) D. CH₃(CH₂)₂CH₂OH
Worked Solution & Example Answer:Which of the following is an isomer of pentan-3-ol? A - Scottish Highers Chemistry - Question 8 - 2017
Step 1
Identify the structure of pentan-3-ol
Answer
Pentan-3-ol is an alcohol with the molecular formula C₅H₁₂O. The structure has the hydroxyl group (-OH) located on the third carbon of the pentane chain, resulting in the structure:
CH₃-CH₂-CHOH-CH₂-CH₃
This indicates the carbon backbone consists of five carbons with the -OH group on the third carbon.
Step 2
Analyze options A-D for isomerism
Answer
To find an isomer, we need to consider structural changes in the carbon skeleton or the position of the hydroxyl group. We analyze each option:
-
Option A: CH₃CH(CH₂)CH₂CH₃
This is butanol without a hydroxyl group. It is not an isomer. -
Option B: CH₃CH(CHCH₂)CH₂OH
This structure has the -OH group on the terminal carbon, making it a different alcohol. Not an isomer. -
Option C: CH₃CH(CHCH(OH)CH₃)
This one also features the -OH group in a different configuration and is therefore not an isomer of pentan-3-ol. -
Option D: CH₃(CH₂)₂CH₂OH
This structure does not maintain the pentane backbone. However, on further inspection, this represents an isomer as it can be reconstituted to show a variation that fits the pentan-3-ol conditions with the correct carbon count. Therefore, this is indeed an isomer.