Your job will be to determine the stoichiometric relationship between the two chemicals and then to subsequently determine whether or not the reaction would produce enough heat to give the sanitation worker second degree burns. Since heat is an extensive property, the amount of heat that is produced depends on the amount of reactants utilized in the reaction. If you have more reactant then you will have more heat. Just think of a big fire cracker versus a small fire cracker. Big boom vs. little boom. In your lab experiment the concentration of both chemicals is going to be 0.5 M, which you should know by now means 0.5 mols/L. The concentration of the chemicals in the dumpster are not 0.5 M, and are given as 6% by mass for sodium hypochlorite and 20.0% by mass for sodium thiosulfate. You need to figure out a way to convert concentration by mass into molarity because that is the concentration unit you are using in your experiment. I'll give you a hint. If a solution is 6% sodium hypochlorite by mass that means that 6 grams out of every 100 grams of solution is sodium hypochlorite.