Ions (Simplified): Videos & Practice Problems

Ions are formed when elements either lose or gain electrons, aiming to achieve a stable electron configuration similar to that of noble gases. Metals typically lose electrons, resulting in positively charged ions known as cations, while nonmetals tend to gain electrons, forming negatively charged ions called anions. This process of electron transfer is driven by the desire for stability in the electron arrangement.

Additionally, the term isoelectronic refers to different elements or ions that possess the same number of electrons. Understanding this concept is crucial when studying ionic formation, as it highlights the relationship between electron configuration and the stability of ions. In summary, the formation of ions through the gaining or losing of electrons is a fundamental concept in chemistry, reflecting the elements' pursuit of a noble gas-like electron arrangement.

When discussing ion formation, it is essential to understand the difference between cations and anions. A cation is formed when an atom loses electrons, resulting in a positive charge. For example, consider boron, which has an atomic mass of 11 and an atomic number of 5. This means boron has 5 protons and, in a neutral state, 5 electrons. If boron loses 3 electrons, it will have 2 electrons remaining. The loss of 3 electrons gives boron a charge of +3, as each lost electron increases the positive charge by one.

On the other hand, an anion is formed when an atom gains electrons, leading to a negative charge. Taking oxygen as an example, it has a mass number of 16 and an atomic number of 8, indicating it has 8 protons and, in a neutral state, 8 electrons. If oxygen gains 2 additional electrons, it will now have 10 electrons in total. This gain of 2 electrons results in a charge of -2 for oxygen, as each gained electron contributes to a more negative charge.

In summary, the key to understanding ion formation lies in recognizing whether electrons are being lost or gained. Cations, like boron with a +3 charge, result from electron loss, while anions, like oxygen with a -2 charge, result from electron gain.

In this example, we are tasked with determining the number of protons, neutrons, and electrons in a cation with a +3 charge. A cation is an ion with a positive charge, indicating that it has lost electrons. The atomic number, represented by the variable z, is given as 13, which tells us that there are 13 protons in this element. This eliminates any options that suggest a different number of protons, such as 27.

The mass number, denoted by the variable a, is provided as 27. The mass number represents the total number of protons and neutrons in the atom. To find the number of neutrons, we can use the formula:

Neutrons = Mass Number - Atomic Number

Neutrons = a - z

Substituting the values, we have:

Neutrons = 27 - 13 = 14

At this point, we know there are 13 protons and 14 neutrons. The charge of +3 indicates that the cation has lost 3 electrons. In a neutral atom, the number of protons equals the number of electrons. Therefore, if aluminum is neutral with 13 electrons, losing 3 electrons results in:

Electrons = 13 - 3 = 10

Thus, we have 13 protons, 14 neutrons, and 10 electrons. To verify the charge, we can calculate:

Charge = Protons - Electrons

Charge = 13 - 10 = +3

This confirms that the calculations are correct. Therefore, the only option that accurately reflects the number of each subatomic particle is option C, which states 13 protons, 14 neutrons, and 10 electrons.