[Chimie]

Hello,
When an amount of CCl4 (g) face radiation with wavelength 3X10 of the power -6.m
Determine if the radiation can dissociate the CCl4 in respect of B.E C-C334 kj/mol ,B.E Cl-Cl 239 KJ/mol , Xcl 3.16 and Xc 2.55
Solution goes like,

1.   Determine the B.E of the compound CCl4
B.E ccl4 = root of B.E c-c *B.E cl-cl    + 96.3*(delta X )square
2.  P = h/mv
3. compare the B.E ccl4 with radiation energy
When the B.E has less value than radiation energy which can be broken the bonds .
I guess so!

What's stopped me to do this strategy is ccl4 state is in gas phase, B.E is calculate to solid state  as born cycle, isn't?
How can I do the B.E of cl-cl when I have 4 atoms?! Should I multiply 4 in the B.E of cl-cl or 2 where the chloride is a molecule or it's cl-cl for molecule?
How can I apply the .  P = h/mv for this compound, is the m for C Or cl2
Chemist do something about it, please.