Which of the following species is largest in radius?1 pointO2-F-NeNa+Mg2+

The size of an atom is determined by the number of electron shells it has, which is determined by the number of electrons. The more electrons an atom has, the larger it is.

1. O2-: This is an oxygen ion with two extra electrons. Oxygen normally has 8 electrons, so this ion has 10 electrons.

2. F-: This is a fluorine ion with one extra electron. Fluorine normally has 9 electrons, so this ion has 10 electrons.

3. Ne: This is a neon atom, which has 10 electrons.

4. Na+: This is a sodium ion that has lost one electron. Sodium normally has 11 electrons, so this ion has 10 electrons.

5. Mg2+: This is a magnesium ion that has lost two electrons. Magnesium normally has 12 electrons, so this ion has 10 electrons.

All of these species have 10 electrons, but the number of protons in the nucleus also affects the size of the atom or ion. The more protons, the more pull on the electrons, and the smaller the atom or ion.

So, the order from largest to smallest is O2- > F- > Ne > Na+ > Mg2+. Therefore, O2- is the largest in radius.