[omfgwtfcamelbbq]

Ok, ive been given some titration questions for homework, and Ive answered all except this one. I not sure about working out the redox pairs. Anyway here is the theory.

Oxidation of wine can be reduced by the addition of SO2 which acts as a reductant and inhibits the action of bacteria. SO2 gas may be added directly as it is soluble in water. Alternatively, sodium metabisulfite may be added to the wine; it reacts with the water and weak acids in wine to produce SO2 in solution. Further reactions may ‘fix’ the SO2 in the form of ‘bisulfite addition compounds’.

In this experiment, NaOH is added to the wine and the resultant mixture is left to stand in order to convert these bisulfite addition compounds to sulfite ions. Then, when sulfuric acid is added, sulfite and hydrogen sulfite ions are converted to SO2 in aqueous solution. In this way, all the SO2 initially added to the wine is available for titration against the standard solution of iodine. The titration must be performed quickly to reduce the loss of SO2  gas.

Question is write the half equations then full equations for
SO2 --->   HSO4-     
I2 ----> 2I-

Anyway i wont write it all down but after balancing water, hydrogen and electrons i come out with the full equation...


SO2 + H2O + I2 ----> HSO4- + 3H+ + 2I-


Is this correct?


Thanks in advance for any answers!

[LQ43]

SO2 + H2O + I2 ----> HSO4- + 3H+ + 2I-


Is this correct?

Almost, O and H are not balanced - but its easy to fix

[omfgwtfcamelbbq]

ah thanks a heap...

SO2 + 2H2O + I2 ----> HSO4- + 3H+ + 2I-

This is the correct equation?

[Borek]

OK now.

[AWK]

SO2 + H2O + I2 ----> HSO4- + 3H+ + 2I-


Is this correct?

Not yet.
Calculate oxygen and hydrogen atoms on both side

[Borek]

SO2 + H2O + I2 ----> HSO4- + 3H+ + 2I-


Is this correct?

Not yet.
Calculate oxygen and hydrogen atoms on both side

Don't scare people - in the last post omfgwtfcamelbbq gave correct equation, you are quoting one from the very beginning of the thread.