Final answer:
All the options provided, Na+, F−, O2−, and Mg2+, end up with the electron configuration of the noble gas neon, meaning none of these ions have a different electron configuration than neon.
Step-by-step explanation:
The student asked which of the following ions does not have the same electron configuration as the noble gas neon: A. Na+, B. F−, C. O2−, D. Mg2+. To answer this question, we need to look at each ion and determine if they have the electron configuration of neon, which is 1s22s22p6.
- Na+ has lost one electron compared to a neutral sodium atom, giving it 10 electrons with a configuration of neon.
- F− has gained one electron compared to a neutral fluorine atom, also resulting in 10 electrons with a configuration of neon.
- O2− has gained two electrons compared to a neutral oxygen atom, once again giving it 10 electrons with a configuration of neon.
- Mg2+ has lost two electrons compared to a neutral magnesium atom, but it started with 12 electrons, so after losing two, it ends up with 10 electrons.
All ions listed are isoelectronic with neon, so none of the options A, B, C, or D will have a different electron configuration from neon, as they all end up with 10 electrons in the same arrangement as neon.