Bond Enthalpies [ENDORSED]

[Taylor_Lam_1E]

For calculating bond enthalpies, is it always required to draw the lewis dot structure, or is there a more efficient way to solve these problems? Thanks!

[Natalie_Boyd_1C]

I think you probably need to draw a Lewis dot structure to figure out what bonds a molecule has, unless you memorize the bonds for a particular molecule. I.e. you probably don't have to draw a Lewis structure for O2, because it's been drawn a lot in class, and we know it has a double bond.