Final answer:
The electron configuration for a fluorine anion (F-) with a -1 charge is 2s2 2p6, which represents a completed second energy level similar to the noble gas neon.
Step-by-step explanation:
The electron configuration for a fluorine anion with a charge of -1 is 2s²2p⁶. A neutral fluorine atom has an atomic number of 9, meaning it has nine electrons. Its electron configuration is 2s22p5, with seven valence electrons. As a member of Group 7A in the periodic table, fluorine tends to gain one electron to achieve a noble gas electron configuration, resembling that of neon. By gaining an additional electron, the fluorine anion, or fluoride, has 10 electrons in total, which completes its second energy level and gives the ion a 1- charge, written as F-. This completed arrangement is known as the noble gas electron configuration.
The electron configuration for a fluorine anion with a charge of -1 can be determined by adding an extra electron to the neutral fluorine atom's electron configuration. The neutral fluorine atom has the electron configuration 2s²2p⁵. Adding an extra electron, we get the electron configuration for the fluorine anion: 2s²2p⁶. The negative charge on the anion indicates that it has gained one electron.