Acetylene (C2H2) is also known as ethyne. It is the simplest alkyne.
Ethyne
Common name of propyne is Methyl-acetylene
Acetylene
Acetylene
Acetylene
Acetylene
The chemical name for C2H3 is ethyne, also known as acetylene.
Why "acetylene"? Why is the compound even called acetylene at all? I see no similarities to the acetyl radical. No methyls, no carbonyls (not even an oxygen atom), nothing. The OED gives the etymology as [f. ACETYL + Gr. -ηνη female descendant, weaker derivative: see -ENE. The Oxford Dictionary of English gives the origin as: mid 19th cen.: from acetic acid + -yl + -ene. Acetylene can be hydrated to acetaldehyde, which contains the acetyl group and may account for the name. Acetyl compounds could, in principle at least, be dehydrated (often a facile reaction, no change in oxidation state) to C2H4 - an unsaturated hydrocarbon (hence -ene) from an acetyl group, hence acetylene.
An acetenyl is an alternative name for ethynyl, a univalent radical derived from acetylene.
Acetylene is a neutral compound.
Acetylene has a linear molecule.