Stage I: `C-C-C-C-C-C`
(i). `underset("Hex-1-yne")(CH_(3)CH_(2)CH_(2)CH_(2)C-=CH)`
(ii). `underset("Hex-2-yne")(CH_(3)CH_(2)CH_(2)C-=CH-CH_(3))`
(iii). `underset("Hex-3-yne")(CH_(3)CH_(2)C-=C CH_(2)CH_(3))`
Stage II: `C-C-overset(C)overset(|)(C)-C-C`
(iv). `underset("3-Methylpent-1-yne")(HC-=C-underset(CH_(3))underset(|)(C)H-CH_(2)-CH_(3))`
Stage III: `C-C-C-overset(C)overset(|)(C)-C`
(v). `underset("4-Methylpent-1-yne")(HC-=C-CH_(2)-underset(CH_(3))underset(|)(C)H-CH_(3))` ltbr. (vi). `underset("4-Methylpent-2-yne")(CH_(3)-C-=C-underset(CH_(3))underset(|)(C)H-CH_(3))`
Stage IV: `C-C-underset(C)underset(|)overset(C)overset(|)(C)-C`
(vii). `underset("3,3-Dimethylbut-1-yne")(HC-=C-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C)-CH_(3)`
Different pairs exhibit position and chain isomerism. For example, (i) and (ii) are position isomers (i) and (iv) are chain isomers, etc.