titration of dissolved oxygen

例句：

1. 1. The chemist used a drop of acid to titrate the solution.
   化学家用一滴酸来滴定溶液。
2. 2. The process of titration is crucial for determining the exact concentration of a substance.
   滴定过程对于确定物质的确切浓度至关重要。
3. 3. The chemical titration was completed after several hours.
   经过几小时后，化学滴定完成了。