错误:
NO2%3A- %2B MnO4%3A- %2B H%3A%2B %3D Mn2%3A%2B %2B NO3%3A- %2B H2O
^
不需要的字符 ('%')NO2%3A- %2B MnO4%3A- %2B H%3A%2B %3D Mn2%3A%2B %2B NO3%3A- %2B H2O
^
不需要的字符 ('%')