Question

Name an element of Group 3A. What does the group designation tell you about the electron configuration of the element?

Short answer

Aluminum (Al) is in Group 3A, which has three valence electrons.

Step-by-step solution

Identify Group 3A on the Periodic Table

Group 3A, also known as Group 13, is a vertical column of elements on the periodic table. The elements in this group include Boron (B), Aluminum (Al), Gallium (Ga), Indium (In), and Thallium (Tl).

Choose an Element from Group 3A

Select any element from Group 3A. Let's choose Aluminum (Al) as an example.

Understand Group Designation

The group designation, such as Group 3A (or Group 13), indicates the number of valence electrons that elements in this group have. These elements typically have three valence electrons.

Determine the Electron Configuration

For elements in Group 3A, the electron configuration ends with three electrons in the outer energy level. For Aluminum (Al), the full electron configuration is \( 1s^2 2s^2 2p^6 3s^2 3p^1 \), illustrating three valence electrons \((3s^2 3p^1)\).

Key concepts

Electron Configuration

Understanding the electron configuration of an element allows us to visualize and understand its electronic structure.
This arrangement specifies where electrons reside around an atom's nucleus, influencing an element's chemical properties and reactivity. For elements in Group 3A, also known as Group 13, the electron configuration pattern is distinctive.
These elements, such as Aluminum (Al), will typically have an electron configuration that ends in three electrons in the outermost shell.
Let's take Aluminum as an example:

• Core electrons: Electrons fill the inner shells first. For Aluminum, the configuration starts as: \(1s^2 2s^2 2p^6\),
• Valence shell: The distinguishing part of their electron configuration ends with \(3s^2 3p^1\), specifically for Aluminum.

Understanding this distribution helps in predicting chemical behavior and bonding possibilities for these elements.

Valence Electrons

Valence electrons are the electrons found in an atom's outermost shell, and these are crucial in dictating how an atom interacts with others.
In the case of the Group 3A elements, there are always three valence electrons. This uniformity among Group 3A elements is a direct result of their position within the periodic table.
Why are valence electrons important?

• The number of valence electrons determines an element's ability to bond with other elements.
• Elements in Group 3A, with their three valence electrons, readily form bonds to complete their outer shell, typically trying to achieve a stable octet configuration.
• In the example of Aluminum, having three valence electrons enables it to form trivalent compounds, binding with other elements to share, gain, or lose electrons.

Hence, the characteristic of having three valence electrons dramatically influences the chemical properties and reactions of these elements.

Periodic Table Groups

Periodic table groups tell us a lot about an element's properties, as elements within the same group share similarities in terms of chemical behavior.
Group 3A, in particular, consists of elements like Boron, Aluminum, Gallium, Indium, and Thallium. Characteristics of Periodic Table Groups:

• Group numbers, such as 3A or 13, inform us about the valence electrons available for bonding. Elements in Group 3A always have three valence electrons.
• This uniformity results in similar chemical properties within the group.
• As we move down Group 3A, the elements get heavier, but they effectively share common electron configuration characteristics involving the three valence electrons.

Understanding the grouping of elements helps predict their reactivity and roles in compounds, making it easier to relate elements based on their group characteristics.