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Chemistry P41 How was it?
- Thread starter xtremeforums
- Start date
What was your fe^2* value of con centration, was it same for that of fe^3+ given in the question. And how did u get the answer for this part??
What about the rate question what did get for the order of reaction of hcl.
- Messages
- 467
- Reaction score
- 101
- Points
- 53
ws ur answer k=25?
becuase that is what i got
No, it's not the same as fe3+,
[Fe3+]=[I-]. And [Fe2+]= 2[I2]
I used mole ratio between reactants. And mole ratio between products.
- Messages
- 467
- Reaction score
- 101
- Points
- 53
bro it is the same becuse yo dont see the overall equaton see the individual half equation hence 1:1
Well, just to make sure.
[Fe3+] = 2x10^-4
and [I2] = 1x10^-2
(This is given in the question)
I got:
[Fe2+] = 2x10^-2 and
[I-] = 2x10^-4
reaction is:
2Fe3+ + 2I- ------------> 2Fe2+ + I2
so Kc = ( [Fe2+]^2 x [I2]) / ([Fe2+]^2 x [I-]^2)
so Kc = {(2x10^-2)^2 x (1x10^-2)} / { (2x10^-4)^2 x (2x10^-4)^2}
Kc = 2.5x10^9 dm3 mol-1
[Fe3+] = 2x10^-4
and [I2] = 1x10^-2
(This is given in the question)
I got:
[Fe2+] = 2x10^-2 and
[I-] = 2x10^-4
reaction is:
2Fe3+ + 2I- ------------> 2Fe2+ + I2
so Kc = ( [Fe2+]^2 x [I2]) / ([Fe2+]^2 x [I-]^2)
so Kc = {(2x10^-2)^2 x (1x10^-2)} / { (2x10^-4)^2 x (2x10^-4)^2}
Kc = 2.5x10^9 dm3 mol-1
Dude, there is a difference between a full equation and equilibrium. There is nothing means half equation when it comes to equilibrium. I mean you have to treat every specie inpendantly.
See, the reactants before equilibrium had the same number of moles, and in the eqn the mol ratio is 1:1. So obviously, I- has to be same as Fe3+. There were nothing of the products in the beginning, so what is produced, has to be in the ratio of 2:1 (between products).
Can u show ur steps
Because, they said equal conc of Fe3+ and I- of 100cm3 each were mixed.
I.e., equal number of moles of Fe3+ and I-,
I think they were just trying to make the question a bit tougher.
I have showed you my steps a little earlier in this thread.
- Messages
- 467
- Reaction score
- 101
- Points
- 53
actually i just did it simply see
100cm^3 is used for all means we can use the concentration instead of mole ratio as volume s the same
then
-I wrote(iam not sure if its correct or not) that fe^3+ and fe^2+ have same concentration
-for the second part i multiplied by 2 for iodine
then i just pluged in the values for 25 the answer
- Messages
- 467
- Reaction score
- 101
- Points
- 53
oder=1
- Messages
- 467
- Reaction score
- 101
- Points
- 53
because when i drew the next curve i got douuble the initial rate that why drawing tangent in the begining of both the graph's.
- Messages
- 467
- Reaction score
- 101
- Points
- 53
addition for sure your talking about last question second part right?
what was ur order and kc answer?
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I found the paper a little tough. I hope the threshold is around 55 
I got the Kc value as 25.
Was the percentage of Al 6% ?
I got the Kc value as 25.
Was the percentage of Al 6% ?