Atomic Number 90 — synonyms, definition
1. atomic number 90 (Noun)
2 synonyms
Th thorium
1 definition
atomic number 90 (Noun) — A soft silvery-white tetravalent radioactive metallic element; isotope 232 is used as a power source in nuclear reactors; occurs in thorite and in monazite sands.
2 types of
metal metallic element
2 types
radiothorium thorium-228
2 parts of
monazite thorite