How to Write 钷 (pǒ) — Meaning “promethium”

Imagine a small piece of promethium metal shaped like a question mark (叵 looks a bit like a box with an opening). Since promethium is a rare and radioactive element, think of it as a "puzzling metal" in a box. The radical 钅 reminds you it's a metal, and the shape of 叵 can help you recall the pinyin pǒ.

Write the left radical 钅 first: two horizontal strokes, then a left-falling stroke, then two short horizontal strokes, and finally a vertical hook (the hook is small). Then write the right part 叵: a horizontal stroke, then a left-falling stroke, then a vertical stroke enclosing the opening, and finally a right-falling stroke inside. A common mistake is to make the radical's hook too large or to forget the final stroke inside 叵.

钷 (promethium) has the right component 叵, while 钍 (thorium) has 土 (tǔ, earth) on the right, and 钎 (drill rod) has 千 (qiān, thousand) on the right. Visually, 钍's right side is a simple cross shape, 钎's right side has a downward stroke through a horizontal line, and 钷's right side looks like an open box with a stroke inside. Their meanings are different: 钷 is a radioactive element, 钍 is another radioactive element, and 钎 refers to a tool.

钷 is used almost exclusively in scientific or technical contexts to refer to the element promethium (atomic number 61). You will see it in terms like 钷元素 (pǒ yuán sù, the element promethium) and 钷盐 (pǒ yán, promethium salts). It is not a common character in daily life because promethium is a rare radioactive element with limited practical applications, mainly in research and some specialized batteries.

Common words containing 钷 include: 钷元素 (pǒ yuán sù) — the element promethium; 钷盐 (pǒ yán) — promethium salts; 钷化合物 (pǒ huà hé wù) — promethium compounds.