I was wondering what I did wrong in the question below:


[Image: http://i.imgur.com/6C1ayQ6.png]


[color=#000000][font=Verdana, Helvetica, sans-serif][size=medium]I divided the bond dissociation energy by two as it produces two Chlorine atoms, and I took the negative of Chlorine's electron affinity to find the sum needed for -443 KJ/mol by solving for x. Any clue what I did wrong?