I am rewriting this question and using dots to make sure that everything lines up correctly so please ignore the dots.

1. name this hydrocarbon
.......CH3...CH3
.......|.....|
CH3-CH-C-CH2-C-CH2-CH3
....|..|.....|
....CH3CH2..CH2
.......|
........CH3
I have come up with normal heptane but I don't think that's right.

2. Name this compound
...CH3
...|
CH=C-CH-CH-CH3
........|
........CH3

3. Name this compound

....H...H
....\.../
.....C=C
..../..\
...CH3..CH2CH3

4. Name this compound

CH3-CH2..H
......\../
.......C=C
....../...\
.....H.....CH2-CH-CH3
...............|
...............CH3

CH3

Pentane

To name the hydrocarbons in the given structures, we follow the guidelines of IUPAC nomenclature.

1. To name the first compound:

- Count the longest continuous chain of carbon atoms, which consists of 7 carbons in this case.
- Number the carbon atoms in the chain, starting from the end closest to the first branch point.
- Identify and name the substituents attached to the main chain.

Based on the given structure, the name of the compound is 2-methylhexane:

CH3-CH(CH3)-CH2-CH(C2H5)-CH3

2. For the second compound:

- Again, count the longest continuous chain of carbon atoms, which consists of 5 carbons.
- Number the carbon atoms, starting from the end closest to the double bond.
- Indicate the position of the double bond by specifying the number of the first carbon involved.

From the structure provided, the name of the compound is 4-methylpent-1-ene:

CH3-CH=CH-CH(CH3)-CH3

3. Moving on to the third compound:

- Identify the longest continuous chain, which consists of 3 carbon atoms.
- Ensure that the double bond has the lowest possible locant, numbering from the end closest to the double bond.
- Name and locate any substituents.

Accordingly, the name of the compound is prop-1-ene:

H H
\ /
C=C
/ \
CH3 CH2CH3

4. Lastly, for the fourth compound:

- Again, determine the longest continuous chain, which includes 6 carbon atoms.
- Number the carbon atoms to give the substituents the lowest possible locants.
- Specify the position of the double bond.
- Name and locate any branches or substituents.

Based on the structure, the name of the compound is 4-methyloct-2-ene:

CH3-CH2-CH=C(CH3)-CH2-CH2-CH3

CH3