Number of possible alkynes with formula C5H8 is
2
3
4
5
Molecular formula −C5H8
CH3−CH2−CH2−CH≡CH 1 - Pentyne
CH3−CH2−C≡C−CH3 2 – Pentyne
H3C−CH3|CH−C≡CH 3 - Methyl - 1 - Butyne