Which of the following has the largest radius?A.NeB.F-C.Mg2+D.Na+

The size of an atom is determined by the number of electron shells it has, and the effective nuclear charge experienced by the outermost electrons. When an atom loses or gains electrons, it becomes an ion.

A. Ne (Neon) is a noble gas with 10 electrons and 10 protons. It has 2 electron shells.

B. F- (Fluoride) is an ion of Fluorine. It has gained one electron, making it have 10 electrons and 9 protons. It also has 2 electron shells.

C. Mg2+ (Magnesium ion) has lost two electrons, making it have 10 electrons and 12 protons. It has 2 electron shells.

D. Na+ (Sodium ion) has lost one electron, making it have 10 electrons and 11 protons. It has 2 electron shells.

In general, cations (positively charged ions) are smaller than their parent atoms because they have fewer electrons, which decreases electron-electron repulsion and allows the protons in the nucleus to pull the remaining electrons closer. Anions (negatively charged ions) are larger than their parent atoms because they have more electrons, which increases electron-electron repulsion and pushes the electrons further from the nucleus.

Therefore, among these, F- (Fluoride) has the largest radius because it has gained an electron, increasing electron-electron repulsion and making it larger than the others.