Propagation help?
12
In year 12 doing free radical substitutions rn, and I do not get propagation at all.
These are the equations for propagation in the halogenation of methane:
CH4 + Cl⬤ → CH3⬤ + HCl
CH3⬤ + Cl2 → CH3Cl + Cl⬤
Why are there 2 reactions? Are they 2 different reactions going on at the same time or something? Why does the top equation only have 1 Cl radical? I honestly have no clue what is going on here lol
These are the equations for propagation in the halogenation of methane:
CH4 + Cl⬤ → CH3⬤ + HCl
CH3⬤ + Cl2 → CH3Cl + Cl⬤
Why are there 2 reactions? Are they 2 different reactions going on at the same time or something? Why does the top equation only have 1 Cl radical? I honestly have no clue what is going on here lol
Reply 1
Havent done this for a while, but propagation is a radical reaction where there is one radical reactant and one radical product, both reactions will occur in the process of the reaction and they are both classed as propagation steps
Reply 2
AsBr2008
OP
12
Original post
by sdfsadsdfHavent done this for a while, but propagation is a radical reaction where there is one radical reactant and one radical product, both reactions will occur in the process of the reaction and they are both classed as propagation steps
So would the CH4 + Cl⬤ → CH3⬤ + HCl reaction happen before the CH3⬤ + Cl2 → CH3Cl + Cl⬤ reaction?
Reply 3
Original post
by AsBr2008So would the CH4 + Cl⬤ → CH3⬤ + HCl reaction happen before the CH3⬤ + Cl2 → CH3Cl + Cl⬤ reaction?
Yes, then the Cl radical will go back to do the first reaction again, or react with the CH3 radical to undergo a termination step,
(edited 1 year ago)
Reply 4
AsBr2008
OP
12
Original post
by sdfsadsdfYes, then the Cl radical will go back to do the first reaction again, or react with the CH3 radical to undergo a termination step
Ohh that makes a bit more sense now. Thanks!
Reply 5
Original post
by AsBr2008Ohh that makes a bit more sense now. Thanks!
No worries, quite a weird concept to understand, but a nice link to physics that is quite cool
Reply 6
AsBr2008
OP
12
Original post
by sdfsadsdfNo worries, quite a weird concept to understand, but a nice link to physics that is quite cool
Oh cool. I was actually going to take alevel physics originally but decided not to. I enjoy this stuff even if it's difficult to understand.
Reply 7
Original post
by AsBr2008Oh cool. I was actually going to take alevel physics originally but decided not to. I enjoy this stuff even if it's difficult to understand.
Ye thats why I enjoy chemistry, its so different from the other stem subjects imo
Reply 8
AsBr2008
OP
12
Original post
by sdfsadsdfYe thats why I enjoy chemistry, its so different from the other stem subjects imo
True. Though I do biology too and there's a fair amount of overlap with organic chemistry and biological molecules (which makes sense)
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