Answer;
Those are the only three straight chain isomers of C6H10.
There are branched chain isomers, but I will not hold you
responsible for those.
So the three are;
Name
|
Lewis structure
|
1-hexyne
|
|
2-hexyne
|
|
3-hexyne
|
|
If we move the triple bond further to the right, we would
start counting in the opposite direction and we would have
2-hexyne again.