Question

question 1 1 pts which of these correctly shows the group of atoms and/or ions in order of decreasing size? $cu^{2+}>cu^{+}>cu$ $cu>cu^{+2}>cu^{+}$ $cu>cu^{+}>cu^{2+}$ $cu^{+}>cu>cu^{2+}$

Explanation:

When comparing the sizes of atoms and ions of the same element, the more electrons removed (the higher the positive charge), the smaller the ion. A neutral atom (\(Cu\)) has more electrons than its cations (\(Cu^{+}\), \(Cu^{2+}\)). For cations of the same element, \(Cu^{2+}\) has lost more electrons than \(Cu^{+}\). As the number of electrons decreases (while the nuclear charge remains relatively the same for the same element), the effective nuclear charge per electron increases, pulling the remaining electrons closer to the nucleus. So, the neutral atom (\(Cu\)) is the largest. Among the cations, \(Cu^{+}\) is larger than \(Cu^{2+}\) because \(Cu^{2+}\) has a higher positive charge and has lost more electrons.

Answer:

\(Cu > Cu^{+}>Cu^{2+}\) (the third option in the given choices)