英语翻译

英语翻译
A 2.50 gram of bronze was dissolved in sulfuric acid.The copper becomes copper (II) sulfate with sulfur dioxide and water the other products.The copper (II) sulfate is then mixed with iodide ion solution to form copper(I)iodide and the triiodide ion(I3-) and sulfate ions.The triiodide ion is next titrated with thiosulfate(S2O3^ 2-) to form iodide ions and S4O6^ 2- ions.Write and balance the equations and calculate the percent by mass of copper in the original sample if 21.5mL of 1.25 M thiosulfate is need in the titration.