氢氧化钠 (qīng yǎng huà nà) — sodium hydroxide, caustic soda

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

This origin belongs to the traditional form 氫; 氢 is its simplified writing.

The traditional form 氫 combines 气 (air; gas) with 輕, which gives the pronunciation qīng; the simplified 氢 is a later shorthand.

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

氧 pairs 气 (gas) with 養 (to nourish), and 養 gives the sound yǎng.

Two or more meaningful parts placed together so that their meanings combine into a new one.

化 shows two person figures, one upright and one upside down, to give the idea of reversal or change.

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

This origin belongs to the traditional form 鈉; 钠 is its simplified writing.

The traditional form 鈉 uses 金 for metal and 內 to give its sound. The simplified 钠 is a later shorthand.