Question

add a methyl substituent at carbon #3, an ethyl substituent at carbon #5, and a propyl substituent at carbon #6 to this organic molecule. be sure your answer is a condensed structure that follows all the usual rules. \\(\ce{ch3-ch2-ch2-ch2-ch2-ch2-ch2-ch2-ch3}\\)

Explanation:

Step1: Identify the parent chain

The parent chain is a straight - chain alkane with 9 carbon atoms (since we have \( \text{CH}_3 - (\text{CH}_2)_7-\text{CH}_3 \), which is nonane, \( \text{C}_9\text{H}_{20} \) in its unsubstituted form).

Step2: Add substituents at the specified carbons

• Carbon #3: A methyl substituent (\( -\text{CH}_3 \)) is added. So the group at carbon 3 becomes \( -\text{CH}(\text{CH}_3)- \) (since the original carbon in the parent chain has 2 hydrogen atoms, and we replace one hydrogen with a methyl group).
• Carbon #5: An ethyl substituent (\( -\text{C}_2\text{H}_5 \)) is added. So the group at carbon 5 becomes \( -\text{CH}(\text{C}_2\text{H}_5)- \) (replacing one hydrogen on the original carbon with an ethyl group).
• Carbon #6: A propyl substituent (\( -\text{C}_3\text{H}_7 \)) is added. So the group at carbon 6 becomes \( -\text{CH}(\text{C}_3\text{H}_7)- \) (replacing one hydrogen on the original carbon with a propyl group).

Now, let's build the condensed structure:

Start from the left (carbon 1: \( \text{CH}_3 \)):

• Carbon 1: \( \text{CH}_3 \)
• Carbon 2: \( \text{CH}_2 \)
• Carbon 3: \( \text{CH}(\text{CH}_3) \) (because of the methyl substituent)
• Carbon 4: \( \text{CH}_2 \)
• Carbon 5: \( \text{CH}(\text{C}_2\text{H}_5) \) (because of the ethyl substituent)
• Carbon 6: \( \text{CH}(\text{C}_3\text{H}_7) \) (because of the propyl substituent)
• Carbon 7: \( \text{CH}_2 \)
• Carbon 8: \( \text{CH}_2 \)
• Carbon 9: \( \text{CH}_3 \)

Putting it all together, the condensed structure is: \( \text{CH}_3\text{CH}_2\text{CH}(\text{CH}_3)\text{CH}_2\text{CH}(\text{C}_2\text{H}_5)\text{CH}(\text{C}_3\text{H}_7)\text{CH}_2\text{CH}_2\text{CH}_3 \)

Answer:

\( \text{CH}_3\text{CH}_2\text{CH}(\text{CH}_3)\text{CH}_2\text{CH}(\text{C}_2\text{H}_5)\text{CH}(\text{C}_3\text{H}_7)\text{CH}_2\text{CH}_2\text{CH}_3 \)