How to Write 巯 (qiú) — Meaning “sulfhydryl; thiol”

Picture a chemist holding a flask (酉) with a liquid that smells like rotten eggs (thiols often stink). The right side 九 looks like the number 9, and you can think "9 sulfur atoms" — though not accurate, it helps recall the chemical meaning. Alternatively, imagine the dot on top of 九 as a sulfur atom floating above.

The left part 酉 must be written with 7 strokes: first a horizontal, then a left-falling line, then a vertical, then three horizontals (the middle one shorter), and finally a horizontal closing the box. The right part is 九 with a dot above it — note that the dot is written before the left-falling stroke of 九. Avoid making the right side too large; keep it balanced.

Common terms include 巯基 (qiú jī, sulfhydryl group), a key functional group in organic chemistry, and 巯基化 (qiú jī huà, thiolation), a chemical reaction. 乙巯 (yǐ qiú, ethanethiol) is a specific compound used as an odorant in natural gas. These terms appear mainly in scientific texts, laboratories, or chemistry classes.

This character is used almost exclusively in scientific and technical contexts, especially in organic chemistry and biochemistry. It appears in research papers, textbooks, and chemical product labels. Unlike common HSK characters, 巯 is not used in daily conversation; you will only encounter it if you study chemistry or work in related fields in China.

Common words containing 巯 include: 巯基 (qiú jī) — sulfhydryl group; thiol group; 巯基化 (qiú jī huà) — thiolation; 乙巯 (yǐ qiú) — ethanethiol (chemical compound).