Is always smaller than atom from which it is formed, whereas is always larger than atom from which it is formed.
The correct answer and explanation is:
The correct answer is:
A cation is always smaller than the atom from which it is formed, whereas an anion is always larger than the atom from which it is formed.
Explanation:
When an atom forms a cation, it loses one or more electrons. This loss results in a positively charged ion. Since electrons are negatively charged and are located in the outermost regions of an atom, when they are lost, the electron cloud shrinks. As a result, the cation becomes smaller than the original atom. This occurs because the loss of electrons reduces the repulsive forces between them, and the remaining electrons are pulled closer to the nucleus, causing the ion to contract in size. Additionally, with fewer electrons than protons, the effective nuclear charge (the attractive force from the nucleus) increases, pulling the remaining electrons even closer.
On the other hand, when an atom forms an anion by gaining one or more electrons, it becomes negatively charged. The addition of electrons increases the electron-electron repulsion in the electron cloud. With more electrons than protons, the attraction between the nucleus and the electrons decreases. As a result, the electron cloud expands, making the anion larger than the original atom. This expansion occurs because the nucleus cannot pull the added electrons as tightly, and the repulsion between the negatively charged electrons pushes them further apart.
The size difference between cations and anions also plays a crucial role in their chemical properties. Cations, being smaller, are often more effective in forming ionic bonds with anions, as their smaller size allows them to interact more easily with other negatively charged particles. Conversely, anions are larger and tend to attract positively charged particles more readily.
This fundamental concept in chemistry is essential when studying ionic compounds and understanding the behavior of ions in various chemical reactions.