错误:
HNO3 %2B Fe%28CrO2%292 %3D H2O %2B NO %2B Fe%28NO3%293 %2B H2CrO4
^
不需要的字符 ('%')HNO3 %2B Fe%28CrO2%292 %3D H2O %2B NO %2B Fe%28NO3%293 %2B H2CrO4
^
不需要的字符 ('%')