错误:
Na%5BCr%28OH%294%5D %2B NaOH %2B Cl2 %3D Na2CrO4 %2B NaCl %2B H2O
^
不需要的字符 ('%')Na%5BCr%28OH%294%5D %2B NaOH %2B Cl2 %3D Na2CrO4 %2B NaCl %2B H2O
^
不需要的字符 ('%')