[Noor]

Hi guys

I am in SERIOUS need of help.

I have these two equations:

Equation 1: S2O8^-2 + 2I^-1 -----> I2 + 2SO4^-2
Equation 2: 2S2O3-2 + I2 ---> 2I^-1 + S4O6^-2

These two reactions come up form this table that we did in this experiment (iodide persulphate reaction)
http://img87.imageshack.us/img87/833/labbbpr4.jpg

I know how to calculate the first 3 columns, but I don't get what it's asking for in the fourth column. We multiply 0.5 by the limiting reagent or what??? I DON"T GET IT!!!

and what do I do with delta t as well?

[Borek]

Delta means change - most likely it asks about the amount of S₂O₈^2- that reacted. This is given by the stoichiometry of the whole process (assuming you have determined amount of iodine produced).

But honestly I don't understand whole procedure, so I am just guessing. Describe what you did in more details.

Oh, and please read forum rules. Crying URGENT is not the best way of starting questions.