Each of the following proposed mechanisms for the free-radical chlorination of methane is wrong. Explain how the experimental evidence disproves each mechanism.
Here, we are going to describe about the experimental evidence for each mechanism.
Step 1: (a)
It requires only one photon of light to generate CH3Cl. Thus the quantum yield for the reaction is only 1.0.
Quantum yield =
But, in actual, the quantum yield is so high which is more than several hundred. Thus, the high quantum yield indicates about a chain reaction.
Therefore, the above reaction is not a chain reaction. It has no propagation steps.