11
Tush Watts
·2009-09-27 23:45:41
@ decoder
nops ans is (c) for Q2
1
decoder
·2009-09-28 06:32:29
sorry a small calculation mistake......ans is (C)
HA + NaOH → NaA + H2O
initial milimoles 20 9 +V/10 0
final 20-(9+V/10) 0 9+V/10
now since ot is an acidic buffer
pH =PKa +log[salt]/[acid]
5=5 +log[salt]/[acid]
[salt]=[acid]
[20-(9+V/10) ]/290+V = [9+V/10]/290+V
v=10ml
11
Tush Watts
·2009-09-28 06:37:54
Thanx a lot decoder, but please try the first one.
3
iitimcomin
·2009-09-28 06:42:43
i mean is the first answer 6.4???
3
iitimcomin
·2009-09-28 06:47:22
sry got my mistake ... soln comin up...
3
iitimcomin
·2009-09-28 06:50:26
i took log 2 as 0.6 by mistake and i didnt see that 25mL thats y i got 6.4 before!!!!! sorry..