The Lewis structure for ethyne (C₂H₂) shown below is incorrect. Starting from this structure, complete the correct structure.

In drawing the Lewis structure for C2H2 (also called ethyne) you'll find that you don't have enough valence electrons available to satisfy the octet for each element (if you use only single bonds). The solution is to share three pairs of valence electrons and form a triple bond between the Carbon atoms in C2H2 .