一氧化碳

• 一(first; number one (pictographic))ASSOCIATIVE

A single horizontal stroke symbolizes the number one, the beginning of all things.

• 气(air; vapor)RADICAL
• 羊(goat)PHONETIC

Gas with a tone like 'dương' is oxygen—the gas that sustains all living things.

• 亻(person; human)RADICAL
• 匕(spoon; compare)PHONETIC

A person standing upright beside a person bending down shows how shapes transform and change.

• 石(stone; rock)RADICAL
• 炭(charcoal; coal)PHONO-SEMANTIC

Carbon is a solid substance like stone, essentially charcoal.