The chemical formula of acetylene is #C_2H_2#. What type of bond holds the two carbon atoms together?

1 Answer
May 4, 2016

Answer:

A #C-=C# triple bond.

Explanation:

Each carbon contributes 4 electrons; each hydrogen contributes 2 electrons. A Lewis representation must therefore distribute 10 electrons: #2xxC-H# bonds, 4 electrons, and #1# #C-=C# triple bond, 6 electrons.

A valence bond formalism would gives rise to 2 #sp# hybrid orbitals on each #C# atom; one such hybrid interacts with #H# to form a #C-H# bond, and the remaining orbital forms a #C-C# bond. The remaining 4 electrons remain unhybridized and forms #pi# bonds above and below the plane of the #C-C# vector.