错误:
Ti2%28SO4%293 %2B Fe2%28SO4%293 %3D Ti%28SO4%292 %2B FeSO4
^不需要的字符 ('%')Ti2%28SO4%293 %2B Fe2%28SO4%293 %3D Ti%28SO4%292 %2B FeSO4
^不需要的字符 ('%')