错误:
AgNO3 %2B Al2%28SO4%293 %3D Al%28NO3%293 %2B Ag2SO4
^
不需要的字符 ('%')AgNO3 %2B Al2%28SO4%293 %3D Al%28NO3%293 %2B Ag2SO4
^
不需要的字符 ('%')