A 1.0 mL volume of 0.010 M H2SO4 is added to a mixture of 6 drops of 0.010 M HIO3, 14 drops of deionized water, and 1 drop of starch solution. A color change in the reaction mixture occurred after 56 seconds.

a. Assuming 20 drops per milliliter for all solutions, determine the initial molar concentration of HIO3 after the mixing but before any reaction occurs (at time = 0).
b. The rate of the reaction is measured by the disappearance of HIO3. For the reaction mixture in this question, what is the reaction rate? Express the reaction rate in units of mol HIO3/L / sec to the correct number of siginificant figures.
Is the answer for part a:
0.010 M x (14 drops/41 drops) = 1.46 x 10-3 M or 1.5 x 10 ^-3 M
As for part b, I'm not sure how to set up this question.
I did balance an equation and have
2 HIO3 + 5 H2SO3 ---> 5 H2SO4 + H2O

2 answers

The 41 drops is correct but not the 14. That's for water. You want HIO3 so it is 0.010 x (6/41) = ?
My bad that was a typo my answer stays the same though. WHat about part b.) ?