2H+
5)
In chemistry, ethenium, protonated ethylene or ethyl cation is a positive ion with the formula C
2H+
5. It can be viewed as a molecule of ethylene (C
2H
4) with one added proton (H+
), or a molecule of ethane (C
2H
6) minus one hydride ion (H−
). It is a carbocation; more specifically, a nonclassical carbocation.