hydrogen ion determination

例句：

1. 1. Thedetermination of the pH value is crucial forunderstanding the chemical properties of the solution.
   pH值的测定对于理解溶液的化学性质至关重要。
2. 2. The determination of the concentration of thesubstance was done using a spectrophotometer.
   使用分光光度计测定了该物质的浓度。
3. 3. The determinationof the reaction rate isessential for predicting the outcomeof the experiment.
   反应速率的测定对于预测实验结果至关重要。