How Do You Calculate the Initial Rate of H2O2 Disappearance?

[chemnerd666]

Homework Statement

In the reaction between H2O2 and I-, 15 mL of 0.30M KI, 75. mL of 0.10M H2O2 and 21 mL of 0.020M Na2S2O3 were mixed in a flask containing starch and buffer and the total volume was made up to 500mL with distilled water. The solution turned blue (indicating the presence of I2) in 1.9 minutes. Calculate the initial rate of disappearance of H2O2 in units of M min-1 to two significant figures.

Homework Equations

Not sure

The Attempt at a Solution

I really have no clue how to answer this question, any help is appreciated.

 

[Borek]

Reaction equation?

Once you have that ready, can you write equation for reaction speed?

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