transition element

American  

noun

Chemistry.

1. any element in any of the series of elements with atomic numbers 21–29, 39–47, 57–79, and 89–107, that in a given inner orbital has less than a full quota of electrons.

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transition element British  

noun

1. chem any element belonging to one of three series of elements with atomic numbers between 21 and 30, 39 and 48, and 57 and 80. They have an incomplete penultimate electron shell and tend to exhibit more than one valency and to form complexes

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transition element Scientific  

/ trăn-zĭsh′ən /

1. Any of the metallic elements within Groups 3 through 12 in the Periodic Table that have an incomplete inner electron shell and that serve as transitional links between the most and the least electropositive in a series of elements. They are characterized by multiple valences, colored compounds, and the ability to form stable complex ions.

2. See Periodic Table See Note at metal

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Etymology

Origin of transition element

First recorded in 1920–25