1
voldy
·2009-01-10 06:39:42
doesn't the value of the rate constant play a role???????
u've given equal importance to all no ?
1
voldy
·2009-01-11 02:11:07
dude. got a doubt . sorry for my Q's but this is what I got when I searched .
Tha presence of pyridine . stops and the Sni reaction which takes please like Sn2.
to yahan , thoda balav aega kya ? aap ka method abhi tak mughe convince nahi hua. please wrtie it in detail . total detail . every step.
please
1
gagar.iitk
·2009-01-10 07:20:07
here SN1 racemises 100%
SN2 gives inversion and
SNi gives retention and it is lesser in % than inversion so it will cause 200% racemisation so
% racemisation == 2* 4*10-6+10-6/10-5+4*10-6+10-6
== 60%
1
gagar.iitk
·2009-01-10 07:14:11
as if single rxn only SN1 causes racemisation but if retention and inversion go hand in hand the lesser causes racemisation
1
voldy
·2009-01-10 07:12:03
Sn1 and Sn2 only causes racemization .
by Sn2 - 10-5 and due to Sn1 - .5* 10-6
no?
1
gagar.iitk
·2009-01-10 07:09:48
it is .5 not 5 it is from half of the SN1
1
voldy
·2009-01-10 07:02:09
Oh sry . Sn2 predominates .given by th rate constnat only. 10-5. messed it up . haan.
then what?
woh 5*10 -6 kahan se aa gaya?
getting it wrong dude.
please give total detail . da.
1
gagar.iitk
·2009-01-10 06:44:33
no u r getting it wrong srinath i am giving imp to rate cons
look % S will be 4*10-6+.5*10-6/sum of all
multi ply it with 2 and get the ans
1
gagar.iitk
·2009-01-10 06:42:10
in case of SOCl2 with a base SN2 predominates
1
voldy
·2009-01-10 06:40:07
here Sn1 predominates no?
1
voldy
·2009-01-10 05:36:33
This reaction proceeds by Sn1 , Sn2 , and Sni right???
so the one which contributes to racemization is only the first and last term , thus % racemization is given by that by the total . no?
1
gagar.iitk
·2009-01-10 06:31:27
look for the question let assume that given comp is R
for Sn1 50% R and 50% S
for Sn2 100% S
for Sni 100% R
there fore % R=30%
%S=70%
% racemisation =2multiplied by % of lesser
1
voldy
·2009-01-10 06:23:42
dude , here's my approach , check out and tell my mistake.
% racemizationis
10-5 + (10 -6 / 2) by 10-5 + ( 4* 10-6 ) + 10-6 / 2
I took it so , coz . in Sn1 . 100% racemization .and in Sn2 , 50% as it's a carbocationic intermediate.
where's the mistake.???? please clarify. this is fianl step after cancelling [ROH] and putting [cl-] = [socl2] =1
this reduces to .21 / 29 . which gives. 72.4 %
1
gagar.iitk
·2009-01-10 06:03:12
no ithink the ans is 60% i have to do it again its a long time i have posted it
1
voldy
·2009-01-10 06:00:55
but a mistake's a mistake. :P
ab sahi hai?????
1
voldy
·2009-01-10 05:59:26
72.4 % ????????? .. I think. is this right?
1
gagar.iitk
·2009-01-10 05:45:38
the reactions u got completely right but i dont know why then ur getting the wrong ans there must be a silli mistake i think try it again
or tell me i will post the solution
1
voldy
·2009-01-10 05:37:11
yeh sahi hain na. atleast approach . bolo yaar.