Question

Consider the following statement: "The ionization energy for the potassium atom is negative, because when \(\mathrm{K}\) loses an electron to become \(\mathrm{K}^{+}\), it achieves a noble gas electron configuration." Indicate everything that is correct in this statement. Indicate everything that is incorrect. Correct the incorrect information and explain.

Short answer

The correct parts of the statement are that when potassium (K) loses an electron to become potassium ion (K+), it achieves a noble gas electron configuration. The incorrect part is that the ionization energy for the potassium atom is negative. Ionization energy is always positive as it requires energy to remove an electron from an atom. The corrected statement is: "The ionization energy for the potassium atom is positive because when potassium (K) loses an electron to become potassium ion (K+), it achieves a noble gas electron configuration."

Step-by-step solution

Rewriting the statement for clarity

Let's rewrite the given statement to better understand it: "The ionization energy for the potassium atom is negative because when potassium (K) loses an electron to become potassium ion (K+), it achieves a noble gas electron configuration."

Understanding Ionization Energy

Ionization energy is the minimum amount of energy required to remove an electron from an atom or ion in its gaseous state. It is generally expressed in electron volts (eV) or kilojoules per mole (kJ/mol). Ionization energy has a positive value because it takes energy to remove an electron from an atom. The more energy it takes, the higher the ionization energy.

Identifying the correct information

The given statement says that when potassium (K) loses an electron to become potassium ion (K+), it achieves a noble gas electron configuration. This is correct. Potassium is an alkali metal with an electron configuration of [Ar] 4s1. By losing one electron, it becomes K+, having an electron configuration of [Ar], which is the same as the noble gas argon.

Identifying the incorrect information & correcting it

The incorrect part of the statement is that "The ionization energy for the potassium atom is negative". As mentioned earlier, ionization energy is the energy required to remove an electron from an atom, and it always has a positive value. Thus, we need to correct this part of the statement: "The ionization energy for the potassium atom is positive because when potassium (K) loses an electron to become potassium ion (K+), it achieves a noble gas electron configuration."

Providing an explanation for the correction

The ionization energy should be positive because it takes energy to remove an electron from an atom. When potassium loses an electron to form a potassium ion, it requires energy to overcome the electrostatic attraction between the negatively charged electron and the positively charged nucleus. This energy required to remove an electron is called ionization energy and has positive values.

Key concepts

Potassium Ion

When a potassium atom loses an electron, it becomes a potassium ion (\( \text{K}^+ \)). This process transforms potassium from a neutral atom into a positively charged ion. Potassium naturally contains 19 electrons, distributed with an electron configuration of [Ar] 4s1. In its atomic state, potassium has * 18 electrons in inner shells* 1 electron in the outermost shell (4s1)
By losing one electron, the outer electron is removed, and the configuration of potassium ion becomes simply [Ar]. This process is crucial in chemistry because it relates to how elements like potassium can participate in forming ionic bonds with other elements. Ions such as potassium ion are common in biological systems and are essential for processes such as nerve impulse conduction.

Noble Gas Electron Configuration

The noble gas electron configuration is a stable and energetically favorable electron arrangement. This is often the goal for atoms as they tend to lose, gain, or share electrons to achieve this configuration. For potassium, its parent noble gas is argon, which has a complete outer electron shell with the electron configuration [Ar].
When potassium loses one electron to form a \( \text{K}^+ \) ion, it gains this stable noble gas configuration. Atoms strive for such stability because it reduces potential energy and results in a more energetically balanced state. This noble gas configuration concept underscores the behavior of many elements in their chemical reactions and is part of the broader principle of achieving electron octets for stability.

Alkali Metals

The alkali metals are a group of elements found in Group 1 of the periodic table. These elements include lithium, sodium, potassium, rubidium, cesium, and francium. As their name suggests, alkali metals are highly reactive, especially with water, forming alkaline (or basic) solutions. They have a single electron in their outermost shell, making them eager to lose that electron to achieve the noble gas configuration of the preceding element in the periodic table.
Potassium, as an alkali metal, displays these characteristic properties:

• It has a low ionization energy, which makes losing its outer electron relatively easy.
• It reacts vigorously with substances such as water and oxygen.
• In its ionic form, it plays a crucial role in biological systems.

Understanding alkali metals' behavior helps to grasp why elements like potassium readily lose an electron to form \( \text{K}^+ \) ions. Their reactivity and tendency to form ions is a key factor in many chemical processes.