How to Write 醛 (quán) — Meaning “aldehyde”

Think of the left side 酉 as a bottle of wine, and the right side 荃 as a 'full' (similar sound to 全 meaning complete). Imagine a scientist saying 'The aldehyde in this wine makes the smell complete.' This links the wine radical to aldehyde's role in odors.

Pay attention to the order: first write the left radical 酉 (7 strokes: horizontal, vertical, left-falling, horizontal fold, horizontal, vertical, horizontal), then the right part 荃 (9 strokes: horizontal, vertical, left-falling, horizontal, horizontal, horizontal, vertical, horizontal, horizontal). The overall shape is balanced but the right side is slightly taller; common mistakes include making the right side too narrow or forgetting the inner horizontal stroke in 酉.

醛 refers to the chemical aldehyde, while 酲 (chéng) means being drunk or having a hangover, and 酴 (tú) means yeast or fermented wine. Visually, 醛 has 荃 on the right (with a 艹 top), 酲 has 呈 (chéng) on the right, and 酴 has 余 (yú) on the right. The radical 酉 is common, but the right components differ in meaning and pronunciation.

醛 appears mainly in scientific and industrial terms, especially in chemistry and medicine, such as 甲醛 (formaldehyde) used in disinfectants and preservatives, and 乙醛 (acetaldehyde) in metabolic processes. It is not common in daily conversation but is essential in lab or environmental discussions; note that 甲醛 is also known for its strong smell in new furniture.

Common words containing 醛 include: 甲醛 (jiǎ quán) — formaldehyde; 醛类 (quán lèi) — aldehydes; 乙醛 (yǐ quán) — acetaldehyde.