Chapter 3, Problem 83E

Hydrogen peroxide is used as a cleaning agent in thetreatment of cuts and abrasions for several reasons. It isan oxidizing agent that can directly kill many microorganisms;it decomposes upon contact with blood, releasingelemental oxygen gas (which inhibits the growthof anaerobic microorganisms); and it foams upon contactwith blood, which provides a cleansing action. In the laboratory, small quantities of hydrogen peroxidecan be prepared by the action of an acid on an alkalineearth metal peroxide, such as barium peroxide:

${\text{BaO}}_2\left(s\right)+2\text{HCl}\left(aq\right)\to {\text{H}}_2{\text{O}}_{\text{2}}\left(aq\right)+{\text{BaCl}}_2\left(aq\right)$

What amount of hydrogen peroxide should result when1.50 g of barium peroxide is treated with 88.0 mL ofhydrochloric acid solution containing 0.0272 g of HClper mL? What mass of which reagent is left unreacted?