• Eka-protactinium

    Full definition of eka-protactinium

    Noun

    eka-protactinium

    (uncountable)
    1. Unbitrium (Ubt), an unsynthesized chemical element with atomic number 123.
    2. Unquadunium (Uqu), an unsynthesized chemical element with atomic number 141.

    Usage notes

    The prefix eka- is used to name predicted but undiscovered elements by specifying the known element above them in the same group of the periodic table.

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