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# Rates watch

1. http://www.a-levelchemistry.co.uk/OC...resources.html

for the how far how fast rate homework question 3 I am getting I2 as first order not zero
because if you compare experiments 1 and 2 the concentration of I2 is x 2 and inital rate x2 and therefore 2^1=2? so 1 st oder
2. (Original post by otrivine)
http://www.a-levelchemistry.co.uk/OC...resources.html

for the how far how fast rate homework question 3 I am getting I2 as first order not zero
because if you compare experiments 1 and 2 the concentration of I2 is x 2 and inital rate x2 and therefore 2^1=2? so 1 st oder
You cannot use experiments 1 & 2 as the iodine concentration does not change!

Compare experiments 2 & 3

Only [iodine] is doubled and the rate does not change.
3. (Original post by charco)
You cannot use experiments 1 & 2 as the iodine concentration does not change!

Compare experiments 2 & 3

Only [iodine] is doubled and the rate does not change.
No it does change for experiment 1 and 2 its from 0.0200 to 0.0400
4. (Original post by otrivine)
No it does change for experiment 1 and 2 its from 0.0200 to 0.0400
no, you are looking at the wrong column. That's H+
5. (Original post by Plato's Trousers)
no, you are looking at the wrong column. That's H+
sorry ok if you compare experiments 2 and 3 for I2 you see that the concentration Of I2 x2 and initial x1 so should give 1st order
6. (Original post by otrivine)
sorry ok if you compare experiments 2 and 3 for I2 you see that the concentration Of I2 x2 and initial x1 so should give 1st order
In experiments 2 & 3 the iodine concentration doubles BUT there is NO CHANGE in the rate.

So iodine does NOT EFFECT the rate.

Rate = k[I2]0
7. (Original post by charco)
In experiments 2 & 3 the iodine concentration doubles BUT there is NO CHANGE in the rate.

So iodine does NOT EFFECT the rate.

Rate = k[I2]0
... or affect it, even...
8. (Original post by Plato's Trousers)
... or affect it, even...
Touché

hoist by my own petard ...

... and a Happy New Year to you.
9. (Original post by charco)
Touché

hoist by my own petard ...

... and a Happy New Year to you.

...or to quote Harvey Denton in League of Gentlemen, "hoist by my own pet toad..."

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