Multiple choice Out of the following which is called Marshalls acid? H2S3O8 H2S2O8 H3S2O8 H2S8O3 Reveal answer Fill a bubble to check yourself B Correct answer Explanation Marshall's acid (peroxodisulfuric acid) has the formula H2S2O8. It contains two sulfur atoms each in +6 oxidation state, linked by a peroxide bridge. It is a strong oxidizing agent.