To name the branched alkanes in the given worksheet, we need to follow the IUPAC (International Union of Pure and Applied Chemistry) nomenclature rules for organic compounds. Here's a step-by-step explanation for each compound:
---
General Rules for Naming Branched Alkanes:
1.
Identify the longest continuous carbon chain (this determines the base name).
2.
Number the carbon atoms in the chain starting from the end that gives the lowest numbers to the substituents.
3.
Identify and name the substituents (branches attached to the main chain).
4.
List the substituents alphabetically in the final name.
5.
Use locants to indicate the position of each substituent on the main chain.
---
Solution for Each Compound:
####
1.
```
H3C—CH—CH3
|
CH3
```
-
Longest chain: 3 carbons → Propane
-
Substituent: Methyl group (CH3) at position 2
-
Name: 2-Methylpropane
Answer: 2-Methylpropane
---
####
2.
```
H3C—CH—CH3
|
CH2—CH3
```
-
Longest chain: 4 carbons → Butane
-
Substituent: Ethyl group (CH2CH3) at position 2
-
Name: 2-Ethylbutane
Answer: 2-Ethylbutane
---
####
3.
```
H3C—CH2—CH2—CH2—CH2—CH3
|
CH2—CH3
```
-
Longest chain: 6 carbons → Hexane
-
Substituent: Ethyl group (CH2CH3) at position 4
-
Name: 4-Ethylhexane
Answer: 4-Ethylhexane
---
####
4.
```
H3C—CH2—CH2—CH—CH2—CH3
|
CH2—CH3
|
CH3
```
-
Longest chain: 6 carbons → Hexane
-
Substituents:
- Methyl group (CH3) at position 4
- Ethyl group (CH2CH3) at position 4
-
Name: 4-Ethyl-4-methylhexane
Answer: 4-Ethyl-4-methylhexane
---
####
5.
```
H3C—CH2—CH—CH2—CH—CH2—CH3
| |
CH3 CH2—CH3
```
-
Longest chain: 7 carbons → Heptane
-
Substituents:
- Methyl group (CH3) at position 3
- Ethyl group (CH2CH3) at position 5
-
Name: 3-Methyl-5-ethyloctane
Answer: 3-Methyl-5-ethyloctane
---
####
6.
```
H3C—CH2—CH2—CH2—CH2—CH2—CH3
| |
CH3 CH3
```
-
Longest chain: 7 carbons → Heptane
-
Substituents:
- Methyl group (CH3) at position 2
- Methyl group (CH3) at position 6
-
Name: 2,6-Dimethylheptane
Answer: 2,6-Dimethylheptane
---
Final Answers:
1.
2-Methylpropane
2.
2-Ethylbutane
3.
4-Ethylhexane
4.
4-Ethyl-4-methylhexane
5.
3-Methyl-5-ethyloctane
6.
2,6-Dimethylheptane
Boxed Final Answer:
\[
\boxed{
\begin{array}{ll}
1. & \text{2-Methylpropane} \\
2. & \text{2-Ethylbutane} \\
3. & \text{4-Ethylhexane} \\
4. & \text{4-Ethyl-4-methylhexane} \\
5. & \text{3-Methyl-5-ethyloctane} \\
6. & \text{2,6-Dimethylheptane} \\
\end{array}
}
\]
Parent Tip: Review the logic above to help your child master the concept of naming organic molecules worksheet.
