[ronvoa101]

Can carbon carbon single bond be broken by any regular chemical reaction?

[dumbsnake]

I'm not sure if I understand your question exactly, but I'll try to answer it as best as I can.  (Anyone can feel free to correct me if I'm wrong, I'll appreciate learning.)

carbon-carbon single bonds can't always be easily broken.  It depends on the structure.  For example, the bonds might be unable to be broken due to sterics or thermodynamics or it might be forbidden by quantum mechanics.  However, in the last case it would be forbidden either by heat or by light and permitted by the other.

[nj_bartel]

combustion?

[James Newby]

organic chemistry can be loosely described as the making or breaking of carbon carbon bonds and there are many examples.

Iodoform reaction, decarboxylation reactions, ring shrinking/ring expanding, pericyclic reactions.  All of these can involve the breaking of C-C bonds and im sure many people can tell you others.

In most of these cases, groups are normally added to carbon to lower its pKa and make it easier to leave ie Iodoform