Indicator

指示剂

Explanation (EN)

A substance that changes colour near the stoichiometric point to signal the endpoint of a titration. [Ch.12 extension: an indicator is itself a weak acid (HInd/Ind⁻) with its own Ka, changing colour over pH ≈ pKa ± 1.]

Explanation (ZH)

在化学计量点附近变色、用以指示滴定终点的物质。【第12章扩展:指示剂本身是弱酸(HInd/Ind⁻),有自己的 Ka,在 pH ≈ pKa ± 1 范围内变色。】

About the IPA

The International Phonetic Alphabet is a standardized system of symbols used to represent the sounds of spoken language.

It helps linguists, language learners, and educators accurately describe pronunciation across languages.

Example: the word "hello" in British English is transcribed as /həˈləʊ/ in IPA.