Questions: Which statement is true regarding the size of atoms and ions? A magnesium ion will be larger than a neutral magnesium atom. A magnesium ion will be smaller than a neutral magnesium atom. A magnesium ion will be the same size as a neutral magnesium atom.

Solution Steps

The question asks about the relative sizes of a magnesium ion and a neutral magnesium atom. We need to determine whether the ion is larger, smaller, or the same size as the neutral atom.

Magnesium (Mg) has an atomic number of 12, meaning it has 12 protons and 12 electrons in its neutral state. When magnesium forms an ion, it typically loses two electrons to become \( \text{Mg}^{2+} \).

When magnesium loses two electrons to form \( \text{Mg}^{2+} \), the resulting ion has fewer electrons than the neutral atom. This loss of electrons reduces electron-electron repulsion and allows the remaining electrons to be pulled closer to the nucleus, resulting in a smaller ionic radius compared to the atomic radius.

Final Answer