Question

If I have a molar concentration of Na2S2O3 of .02M and a volume of .001L. As well as a Molar Concentration of KI .3M and H2O2 of .1M. The equation of the reaction is 2S2O3+I3 ->3I+S4O6. The question is "How many moles of S2O3 are consumed". Do I just use the Molar concentration and the volume of the Na2S2O3?

Answer 1

You have to use everything that is given since you have to know which is the limiting reactant. We find the limiting reactant by calculating the number of moles of each reactant and compare the number of moles. The limiting reactant would be the one that is consumed fully by the reaction.