本文提出甲酸还原无色钼磷酸作为催化动力学吸光光度法测定超痕量金的指示反应。建立了维持准零级反应的最佳实验条件,催化反应的速率表达式为V_c=k_c,各试剂的浓度在反应过程中近似不变,它们决定催化反应速率常数的大小。本法灵敏度高,可以检测低至5×10~(-2)ng的金。设备简单,操作方便。 In this paper, colorless and molybdophosphoric acid from formic acid is proposed as an indicator reaction for the determination of ultra trace gold by catalytic kinetic spectrophotometry. The optimal experimental conditions for the quasi zero order reaction were set up. The rate of the catalytic reaction was V_c = k_c. The concentration of each reagent in the reaction was approximately the same, which determined the rate constant of the catalytic reaction. This method is highly sensitive and can detect gold down to 5 × 10 -2 ng. Equipment is simple, easy to operate.