chlorination mechanism

chlorination occur by free radical mechnism whre following steps take place
a) INITIATION STEP
Cl₂------->2Cl^.
b) PROPAGATION STEPS
CH₄+Cl^.------------->CH₃^.+HCl
CH₃^.+Cl-Cl------->CH₃Cl+Cl^.............1
c) TERMINATION STEP
CH₃^.+Cl^.----------->CH₃Cl
CH₃^.+CH₃^.--------->CH₃-CH₃.........2

FRM 1 & 2 CLEARLY CHLOROMETAHNE & ethane r frmed

bt following steps may also take place

CH₃Cl+Cl^.----------->CH₂Cl₂

SO DICHLOromethane is also formed similarly tri & tetra substituted compounds can b obtained

also H^.+H^.----------->H₂

is another possibility but i think H₂will b very less

in 2 mny ptoducts can b obtained use above free radical mechanism try to do it urself u will find it very interesting otherwise i m always there :D

See there are two mechanism of chlorination of methane...
1st one is:-
1a) Cl(free radical) + CH₄ → HCl + CH₃(free radical)
1b) CH₃(free radical) + Cl₂ → CH₃Cl + Cl(free radical)
and further so on.

another mechanism is :-
2a) Cl(free radical) + CH₄ → CH₃Cl + H(free radical)
2b) H(free radical) + Cl₂ → HCl + Cl(free radical)

1st mechanism yields chloromethane, dichloromethane and so on while 2nd one can yield hydrogen......

But the thing is which reaction is followed.... And it depends on relative rates of the reactions...
the one mechanism followed is the faster one....
1st mechanism predominates hence choromethane, dichloromethane and others are major product while hydrogen is not yielded much......

is there is a possibility of forming hydrogen gas?

No!!

No Hydrogen formation ...
Nahi to aag lag jaega :P

just joking..

Mechanism is.....

step1 (chain initiation)

Cl₂ → 2Cl^.

Step 2 (chain prorogation)

Cl^.+CH₄→ HCl+CH₃^.
CH₃^.+Cl₂→CH₃Cl+Cl^.
.......here no H^. formation
Step 3 (Chain termination)

2CH₃^.→CH₃CH₃
2Cl^.→Cl₂