Worksheet on naming alkanes with examples and structural analysis.

Problem Description:

The task involves naming alkanes based on their structural formulas. The worksheet provides two structural formulas of alkanes, and the goal is to name them correctly using IUPAC nomenclature rules.

---

Step-by-Step Solution:

#### 1. First Alkane Structure:
The given structure is:
```
CH3
|
H3C-CH2-CH2-CH2-CH3
| |
CH3 CH3
```

##### Steps to Name:
1. Identify the Longest Continuous Carbon Chain:
- The longest continuous carbon chain in this structure has 6 carbon atoms.
- This makes the base name hexane (since "hex" means six).

2. Locate and Number the Carbon Atoms:
- Start numbering the carbon atoms from the end that gives the lowest numbers to the substituents.
- Here, numbering from the left gives:
```
1-CH3
|
2-CH2-CH2-CH2-CH3
| |
4-CH3 5-CH3
```

3. Identify Substituents:
- There are three methyl groups (`CH3`) as substituents.
- Their positions are:
- One methyl group at carbon 2.
- One methyl group at carbon 4.
- One methyl group at carbon 5.

4. Name the Substituents:
- Methyl groups are named as "methyl."

5. Combine the Information:
- The full name is constructed by listing the substituents in alphabetical order and indicating their positions.
- The name is: 2,4,5-trimethylhexane.

##### Final Answer for the First Alkane:
$$
\boxed{2,4,5-\text{trimethylhexane}}
$$

---

#### 2. Second Alkane Structure:
The given structure is:
```
CH3
|
H3C-CH2-CH2-CH2-CH2-CH3
| |
CH3 CH3
```

##### Steps to Name:
1. Identify the Longest Continuous Carbon Chain:
- The longest continuous carbon chain in this structure has 6 carbon atoms.
- This makes the base name hexane (since "hex" means six).

2. Locate and Number the Carbon Atoms:
- Start numbering the carbon atoms from the end that gives the lowest numbers to the substituents.
- Here, numbering from the left gives:
```
1-CH3
|
2-CH2-CH2-CH2-CH2-CH3
| |
3-CH3 5-CH3
```

3. Identify Substituents:
- There are two methyl groups (`CH3`) as substituents.
- Their positions are:
- One methyl group at carbon 3.
- One methyl group at carbon 5.

4. Name the Substituents:
- Methyl groups are named as "methyl."

5. Combine the Information:
- The full name is constructed by listing the substituents in alphabetical order and indicating their positions.
- The name is: 3,5-dimethylhexane.

##### Final Answer for the Second Alkane:
$$
\boxed{3,5-\text{dimethylhexane}}
$$

---

Summary of Answers:

1. For the first alkane: 2,4,5-trimethylhexane
2. For the second alkane: 3,5-dimethylhexane

$$
\boxed{2,4,5-\text{trimethylhexane}, \quad 3,5-\text{dimethylhexane}}
$$