Final answer:
The electron configuration of a calcium atom is [Ar]4s². For a Ca₂+ ion, after losing two valence electrons, the configuration becomes [Ar], indicating a bond order of 0, which makes the existence of Ca₂+ as a diatomic molecule unlikely.
Step-by-step explanation:
The electron configuration of a calcium atom is crucial for understanding its chemical behavior. Calcium (Ca) with atomic number 20 is found in Period 4 and Group 2 of the Periodic Table and thus follows the general rules for electronic configurations. According to these rules, the calcium's electron configuration would be [Ar]4s².
When predicting the electron configuration of the Ca₂+ ion, we would expect the removal of two electrons from the valence shell (4s²) of a neutral calcium atom. Therefore, the electron configuration for the Ca₂+ ion would simply be the configuration of [Ar], which is the noble gas that precedes calcium in the periodic table. This configuration also indicates a bond order of 0 as there are no 4s electrons involved in bonding and suggests that the Ca₂+ ion is unlikely to exist as a diatomic molecule under normal conditions.