Which element has the electron configuration [Kr] 5s^2 4d^1?

The correct electron configuration for a given element provides insight into its placement in the periodic table and its chemical properties. The electron configuration presented here is [Kr] 5s² 4d¹. The notation [Kr] indicates that the electron configuration up to krypton, which accounts for the first 36 electrons, has been filled. After krypton, the configuration highlights that the next electrons fill the 5s orbital (2 electrons) and the 4d orbital (1 electron).

To determine which element corresponds to this configuration, we need to count the total number of electrons represented in the configuration. Starting with krypton (36 electrons), the configuration shows 2 additional electrons in the 5s subshell and 1 electron in the 4d subshell, leading to a total of 39 electrons. The element with 39 electrons is yttrium, which is located in group 3 of the periodic table.

Yttrium's placement and its electron configuration highlight its position in the d-block transition metals, where it exhibits properties characteristic of such elements. This understanding of electron configuration helps to categorize and predict chemical behavior and reactivity patterns.