acid base indicator

例句：

1. 1. ThepH test is an important tool for determiningthe acidity of a solution.
   pH测试是确定溶液酸度的重要工具。
2. 2. Thechemical reaction between acids and bases isused to create this indicator.
   酸与碱之间的化学反应用于制造这种指示剂。
3. 3. Thecolor change of the indicator can indicate whetherthe solution is too acidic or toobasic.
   指示剂的颜色变化可以指示溶液是否过酸或过碱。