Crossword puzzle clue "astatine and vanadium"

ELEMENT, a substance that cannot be separated into simpler substances by chemical means

any of various elementary substances with particular properties made of metal

HALOGEN, any of the group of elements fluorine, chlorine, bromine, iodine, and astatine

any of the group of elements fluorine, chlorine, bromine, iodine, and astatine

a radioactive element, an inert gas

RARE, not common

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