错误:
K2CO3 %2B C4H9COOH %3D H2O %2B CO2 %2B K%28C4H9COO%29
^不需要的字符 ('%')K2CO3 %2B C4H9COOH %3D H2O %2B CO2 %2B K%28C4H9COO%29
^不需要的字符 ('%')