酚酞 (fēn tài) — phenolphthalein
Definition
A chemical indicator (化学指示剂) used in titrations: colorless in acid, turning pink in basic solutions.
noun
phenolphthalein
Examples
- 酚酞。fēn tài Shì yì zhǒng cháng yòng de zhǐ shì jì.Phenolphthalein is a commonly used indicator.
- ,酚酞。Zài suān xìng róng yè zhōng, fēn tài shì wú sè de.In acidic solutions, phenolphthalein is colorless.
- 酚酞。fēn tài Yù dào jiǎn huì biàn chéng fěn hóng sè.Phenolphthalein turns pink when it encounters alkali.
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