Question

Use noble gas and spdf notations to depict electron configurations for the following metals of the third transition series. (a) Tantalum, Ta. The metal and its alloys resist corrosion and are often used in surgical and dental tools. (b) Platinum, Pt. This metal was used by preColumbian Indians in jewelry. Now it is still used in jewelry but it is also the basis for anticancer drugs and catalysts (such as those in automobile exhaust systems).

Short answer

Ta: \([\text{Xe}] \, 4f^{14} \, 5d^{3} \, 6s^{2}\), Pt: \([\text{Xe}] \, 4f^{14} \, 5d^{9} \, 6s^{1}\).

Step-by-step solution

Identify Element's Atomic Number

First, identify the atomic number of the metal. Tantalum (Ta) has an atomic number of 73, while Platinum (Pt) has an atomic number of 78.

Determine Noble Gas Preceding the Metal

For both Tantalum and Platinum, the noble gas preceding them in the periodic table is Xenon (Xe), which has an atomic number of 54.

Understand spdf Notations

The spdf notation represents the distribution of electrons in a particular atom within its subshells. The 'spdf' letters denote the type of subshell (s, p, d, f) and the number associated with each letter indicates the number of electrons in that subshell.

Determine Electron Configuration for Ta

Following Xe, count up from atomic number 55 to 73 to fill each subshell. Hence, the electron configuration for Tantalum, Ta, in spdf notation is: \[ \text{Ta}: [\text{Xe}] \, 4f^{14} \, 5d^{3} \, 6s^{2} \]

Determine Electron Configuration for Pt

Following Xe, count up from atomic number 55 to 78 to fill each subshell. Hence, the electron configuration for Platinum, Pt, in spdf notation is: \[ \text{Pt}: [\text{Xe}] \, 4f^{14} \, 5d^{9} \, 6s^{1} \]

Verify the Stable Configurations

Review the configurations to ensure they reflect a stable distribution of electrons in accordance with the Aufbau principle, Hund's rule, and Pauli's exclusion principle. Both Ta and Pt configurations reflect their stable electron arrangements.

Key concepts

Noble Gas Notation

Noble gas notation is a shorthand method for depicting electron configurations of elements by beginning with the symbol of the nearest noble gas that precedes the element in the periodic table. This serves as a useful abbreviation, especially for heavier elements with many electrons. Noble gases include elements like He, Ne, Ar, Kr, Xe, and Rn, which have full valence shells. In noble gas notation, instead of writing out all of the configuration, we start with the noble gas in brackets; for example, - Xenon (Xe) serves as the starting point for elements like Tantalum and Platinum. This approach helps simplify the depiction of an element's electron configuration by 'jumping' past filled inner shells, which allows one to focus on the electron occupancy in the outermost shells. The ease of understanding offered by noble gas notation makes it an essential skill for anyone studying chemistry, particularly when dealing with elements in the transition series like Tantalum and Platinum.

spdf Notation

The spdf notation is an essential method for describing the electron configuration of atoms. Each atom's electrons are arranged in subshells denoted by the letters 's', 'p', 'd', and 'f'. Here are simple details to remember:- The **'s'** subshell can hold 2 electrons.- The **'p'** subshell can hold 6 electrons. - The **'d'** subshell can hold 10 electrons. - The **'f'** subshell can hold 14 electrons.Using this notation, the distributions of electrons can be described precisely. The numbers preceding these letters indicate the principal energy level of those subshells.For Tantalum (Ta), the spdf notation is \[\text{Ta}: [\text{Xe}] \, 4f^{14} \, 5d^{3} \, 6s^{2}\]And for Platinum (Pt), it is \[\text{Pt}: [\text{Xe}] \, 4f^{14} \, 5d^{9} \, 6s^{1}\].These configurations reveal how electrons fill the available subshells, providing insight into the chemical properties and behaviors of the elements.

Transition Metals

Transition metals are unique elements found in the d-block of the periodic table. They are characterized by having partially filled d subshells either in their elemental form or in their common oxidation states. Transition metals include familiar elements like iron, copper, silver, and gold, as well as Tantalum and Platinum. Here are important characteristics of transition metals: - Variable oxidation states: They can form compounds in different states. - Complex ion formation: They often form complex ions with various geometries. - Colored compounds: Many compounds of transition metals exhibit vibrant colors due to d-electron transitions. The involvement of d electrons in bonding and the filling of the d subshells lead to these unique properties. For Tantalum (Ta) and Platinum (Pt), their electron configurations highlight the occupation of the d orbitals, which plays a central role in their chemical behavior and applications.

Aufbau Principle

The Aufbau principle, translated from German as "building up", is a guideline for the order in which electrons fill atomic orbitals. According to this principle, electrons occupy the lowest energy orbitals first before moving to higher ones. It follows a systematic pattern which can be understood with the following sequence:- Electrons fill orbitals in the order of increasing energy levels, starting from 1s, then moving onto 2s, 2p, 3s, and so forth.- This rule helps predict the placement of electrons in different subshells for ground-state atoms, often visualized with an Aufbau diagram.For example, both Tantalum (Ta) and Platinum (Pt) exhibit electron filling that respects this principle:- Ta: \[\text{Ta}: [\text{Xe}] \, 4f^{14} \, 5d^{3} \, 6s^{2}\]- Pt: \[\text{Pt}: [\text{Xe}] \, 4f^{14} \, 5d^{9} \, 6s^{1}\]This is in agreement with the principle, as electrons fill from lower to higher energy sublevels, confirming their stable electron configurations.Understanding the Aufbau principle allows students to comprehend how elements are organized and how their chemical properties are derived from their electronic arrangements.