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碳酸 (tàn suān) — carbonic acid; carbonate

Definition

Refers both to carbonic acid (H₂CO₃, a weak acid in drinks) and to carbonate salts/compounds. Context — 气体, 盐, or 饮料 — disambiguates which sense applies.

noun
carbonic acidcarbonate

Examples

  • 碳酸。
    tàn suān Shì yǐn liào zhōng cháng jiàn de ruò suān.
    Carbonic acid is a common weak acid in beverages.
  • 碳酸。
    tàn suān Yán zài zì rán jiè zhōng guǎng fàn cún zài.
    Carbonate salts are widely present in nature.
  • 碳酸。
    Zhè ge fǎn yìng huì chǎn shēng tàn suān qì tǐ.
    This reaction produces carbonic acid gas.

Origin

Compound word
构词法gòucífǎ
偏正piānzhèngModifier + head

The first part narrows down the second: it says what kind of thing the head is.

碳tàncarbon
酸suānacid

碳 points to carbon and 酸 points to acid, so 碳酸 names carbonic acid or a carbonate.

Characters in this word

Two or more meaningful parts placed together so that their meanings combine into a new one.

  • 石石shí{{qualifier|chemical nomenclature}} non-metal solid
  • 炭炭tàncharcoal

碳 pairs 石, marking a non-metal solid, with 炭 (charcoal), which gives the pronunciation.

Open 碳 →

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

Meaning part形符xíngfú
酉酉yǒu
Sound part声符shēngfú
夋
夋qūn酸suān
The sound has drifted apartThe sound part was a clue two thousand years ago — it often still helps, but not always.

酸 is built from 酉 and 夋, and 夋 gives the sound.

Open 酸 →
Appears in
Physics & Chemistry

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