How to Write 氟 (fú) — Meaning “fluorine”

Imagine a gas cloud (气) that is "foul" — the word sounds like fú — because fluorine gas has a sharp, irritating smell. This connects the character's sound and its meaning as a reactive gas.

Pay attention to the stroke order of the right part 弗: left-falling, horizontal, horizontal fold, vertical, then final left-falling. A common mistake is to write the 气 radical too tall or to forget the hook in the third stroke of 弗.

All three share the 气 radical for gas, but the right parts differ: 氟 uses 弗 (fluorine), 氙 uses 山 (xiān, xenon), and 氚 uses 川 (chuān, tritium). Their meanings are different chemical elements, so use the correct character based on the element.

氟 appears in words like 含氟 (hán fú, contains fluorine) and 氟化物 (fú huà wù, fluoride), often seen on toothpaste labels. It is also in 氟利昂 (fú lì áng, Freon), though this refrigerant is now restricted in many countries due to environmental concerns.

Common words containing 氟 include: 含氟 (hán fú) — contains fluorine; 氟化物 (fú huà wù) — fluoride; 氟利昂 (fú lì áng) — Freon.