Final answer:
Yes, anions of different elements can have the same valence electron arrangement, such as the chloride and sulfide ions both achieving the electron configuration of argon. This occurs when they gain electrons to complete their outer shell, mimicking a noble gas configuration.
Step-by-step explanation:
Yes, anions of two different elements can have the same valence electron arrangement. This happens when elements gain the same number of electrons to achieve a noble gas electron configuration. An example of this is the chloride ion (Cl-), which has the same electron arrangement as the argon atom, and the sulfide ion (S2-), which also ends up with the same electron configuration as argon once it has gained two electrons. Both anions have the electron configuration of 3s23p6.
Ions form when atoms gain or lose electrons to achieve a full outer shell, typically resembling the electron configuration of the closest noble gas. In the process of forming anions, nonmetals with a high electronegativity tend to gain electrons, resulting in a valence shell that is identical to the noble gas at the end of their period.
Cations and anions differ in that cations are positively charged ions formed by the loss of one or more electrons, often by metals, whereas anions are negatively charged ions formed by the gain of one or more electrons, often by non-metals. Sodium ion (Na+) is an example of a cation, and the fluoride ion (F-) is an example of an anion.