Problem 72 - Chemistry: The Central Science

Question

Identify the group of elements that corresponds to each of the following generalized electron configurations: (a) [noble gas] \(n s^{2} n p^{5}\) (b) [noble gas] \(n s^{2}(n-1) d^{2}\) (c) [noble gas] \(n s^{2}(n-1) d^{10} n p^{1}\) (d) [noble gas] \(n s^{2}(n-2) f^{6}\)

Step-by-Step Solution

Answer

The groups corresponding to each generalized electron configuration are: (a) Group 17 (Halogens) (b) Group 4 (Transition metals) (c) Group 13 (d) Sixth element within its respective inner transition metals series (Lanthanides or Actinides)

Step 1: (a) Identify the group with electron configuration [noble gas] \(n s^{2} n p^{5}\)

For this case, the electron configuration only states that it needs one more electron in the \(n p\) shell to achieve a complete configuration of the noble gases' shell. This means the element belongs to the group just before the noble gases, which is halogens. Therefore, the group corresponding to this electron configuration is Group 17.

Step 2: (b) Identify the group with electron configuration [noble gas] \(n s^{2}(n-1) d^{2}\)

Here, the element has 2 electrons in the \(d\) shell, which means that it is part of the transition metals. The electron configuration suggests that this element has two extra electrons after the noble gas configuration. So, the element belongs to Group 4.

Step 3: (c) Identify the group with electron configuration [noble gas] \(n s^{2}(n-1) d^{10} n p^{1}\)

In this case, we have a complete filled \(d\) shell and one additional electron in the \(n p\) shell. This suggests that the element belongs to the group just after the noble gases. Thus, the element corresponds to Group 13.

Step 4: (d) Identify the group with electron configuration [noble gas] \(n s^{2}(n-2) f^{6}\)

This electron configuration indicates the element is part of the inner transition metals with electrons in the \(f\) shell. Although inner transition metals, like Lanthanides and Actinides, are not placed in the main columns of the periodic table, the electron configuration can provide information about the relative position within their series. The element has 6 electrons in the \(f\) shell, suggesting that it is the sixth element within its respective series (Lanthanides or Actinides).

Key Concepts

Halogens

Halogens are a fascinating group of elements sitting in Group 17 of the periodic table. They are known for being just one electron short of achieving a full outer shell, similar to noble gases. This is reflected in their generalized electron configuration:

• [noble gas] \(n s^{2} n p^{5}\)

This means halogens have 5 electrons in their outermost p-shell. As a result, they are very reactive and readily gain an electron to form negative ions (anions). Halogens like Fluorine, Chlorine, and Bromine are known for their vivid colors and are found in various everyday substances from table salt to disinfectants. Their diversity and reactivity make them essential in many chemical reactions.

Transition Metals

Transition metals occupy the central part of the periodic table, covering groups 3 to 12. With their electron configuration usually looking something like:

• [noble gas] \(n s^{2}(n-1) d^{x}\)

where \(x\) can vary from 1 to 10, they demonstrate unique properties. Transition metals are characterized by their ability to form colorful compounds, possess multiple oxidation states, and to act as good conductors of electricity. Iron, Copper, and Gold, are well-known for their everyday commercial and industrial uses. Their versatile chemistry allows them to form complex compounds, essential in catalysis and biological systems.

Lanthanides

Lanthanides, also known as rare earth elements, belong to the group of inner transition metals. Their general electron configuration follows:

• [noble gas] \(n s^{2}(n-2) f^{x}\)

where \(x\) is typically between 1 and 14. These elements are well-known for their magnetic, phosphorescent, and catalytic properties. They're less known than other elements but are indispensable in modern technology, including electronics, optics, and as catalysts in industrial processes. The Lanthanide series starts right after Lanthanum and dovetails into the early actinide series, displaying similar chemical properties.

Group 17

When we talk about Group 17, we are directly referring to the halogen family, with their distinctive

• [noble gas] \(n s^{2} n p^{5}\)

electron configuration. The elements in Group 17 include fluorine, chlorine, bromine, iodine, and astatine. These elements are not only reactive but are found in making essential compounds like salts (halides). Their unique position in the periodic table means they play critical roles in a range of biological and industrial applications. They eagerly pair up with alkali and alkaline earth metals to form ionic compounds.

Inner Transition Metals

Inner transition metals encompass the Lanthanides and Actinides, which are located beneath the main body of the periodic table. These elements fill their f subshells, as seen in this typical electron configuration:

• [noble gas] \(n s^{2}(n-2) f^{x}\)

where \(x\) denotes the number of electrons in the f subshell. Inner transition metals are renowned for unique properties such as atomic size and the ability to form complex ions. They are even used in industries, from nuclear power in the form of uranium to the manufacturing of strong magnets and luminescent materials. Through the completion of their f orbitals, these metals showcase interesting chemistry and are a key focus in material science research.