酸化
さんか · sanka · JLPT N3 · noun
oxidation
🔥 酸化 = acid/oxygen (酸) + change (化): becoming oxidised
酸 means sour or acid, and it is also the first kanji of 酸素 (さんそ), oxygen, which literally means acid element. 化 means to change or turn into, like -ize. So 酸化 is changing by oxygen: oxidation, as in rust or burning.
酸 — wine/jar radical 酉 + 夋 (phonetic)
酸 is a semantic-phonetic compound. The left side 酉 depicts a wine jar and signals meanings related to fermentation and alcohol. The right side 夋 supplies the sound. Originally describing the sour taste of fermented wine, it broadened to mean 'sour' in general and figuratively 'aching' or 'sad'.
化 — person 亻 + spoon/upside-down person 匕
化 is an associative compound showing a standing person 亻 next to 匕, originally a depiction of a person turned upside-down. Together they suggest a figure transforming from one state to another, giving the core meaning 'change' or 'transform'. The character later extended to senses like 'convert', 'influence', and the noun suffix '-ization'.