The 2+ ions of transition elements are common. Explain why this might be expected.
Transition elements are those that are in the d-block of the periodic table. These are the elements with valence electrons that are in the d-orbitals. These have different properties as compared to the main group elements (those in the s- and p-blocks).
Answer and Explanation: 1
When filling out the orbitals for transition metals, the last orbital that we fill are the d-orbitals because according to Madelung's rule, those with a higher n+l will be filled last. For instance, 3d orbital has a higher n+l (3 + 2 = 5) than the 4s orbital (4 + 0 = 4). However, when forming ions, the electrons at the 4s orbital are removed first because they are in the higher energy level (4 for 4s and 3 for 3d). Since there are two electrons in the 4s orbital, they are often removed first forming ions with +2 charges. As such, +2 is a common charge for transition metals.
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fromChapter 3 / Lesson 7
Learn what a main group element is, what transition metals are, and compare the two. Explore their definitions, properties, and into which groups they fall.