Question

\(\mathrm{E}\) The "Chemistry in Focus" segment The Chemistry of Bohrium discusses element \(107,\) bohrium \((\mathrm{Bh}) .\) What is the expected electron configuration of Bh ?

Short answer

The expected electron configuration for bohrium (Bh, element 107) is: \[1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^{10} 5p^6 6s^2 4f^{14} 5d^{10} 6p^6 7s^2 5f^{14} 6d^5\]

Step-by-step solution

Identify the order of orbital filling

To determine the electron configuration of bohrium (element 107), we must first understand the order in which electron orbitals fill. This can be remembered using the following sequence: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p

Fill in the orbitals

Now, we can fill in the electron orbitals for bohrium, element 107, following the order mentioned above until we reach 107 electrons: 1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁶, 5s², 4d¹⁰, 5p⁶, 6s², 4f¹⁴, 5d¹⁰, 6p⁶, 7s², 5f¹⁴, 6d⁵ Let's break down the total electron count: 2 (1s²) + 2 (2s²) + 6 (2p⁶) + 2 (3s²) + 6 (3p⁶) + 2 (4s²) + 10 (3d¹⁰) + 6 (4p⁶) + 2 (5s²) + 10 (4d¹⁰) + 6 (5p⁶) + 2 (6s²) + 14 (4f¹⁴) + 10 (5d¹⁰) + 6 (6p⁶) + 2 (7s²) + 14 (5f¹⁴) + 5 (6d⁵) = 107 electrons

Write the final electron configuration

Following the correct order of orbital filling and ensuring that the total number of electrons is 107, the electron configuration for bohrium (Bh, element 107) is: \[1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^{10} 5p^6 6s^2 4f^{14} 5d^{10} 6p^6 7s^2 5f^{14} 6d^5\]

Key concepts

Bohrium

Bohrium, denoted as Bh, is a synthetic chemical element with the atomic number 107. It is part of a group known as the transactinide elements, and it is placed within the d-block of the periodic table, particularly in the 7th period. Bohrium is classified as a transition metal and remains largely unexamined due to its rarity and instability.
It was named in honor of the Danish physicist Niels Bohr, a pioneer who had a significant influence on the understanding of atomic structure and quantum theory. Some key points about Bohrium:

• It is not found naturally on Earth and must be artificially synthesized.
• Bohrium atoms are produced in particle accelerators by bombarding heavier elements such as bismuth with ions such as chromium.
• The study of bohrium involves understanding its electron configuration for theoretical comparisons and predictions about its chemical behavior.

Order of Orbital Filling

To determine the electron configuration of an element like bohrium, we need to follow the order of orbital filling. Electrons fill atomic orbitals in a specific order according to the Aufbau Principle. This principle suggests that electrons occupy the lowest energy orbital available first. A helpful tool for remembering this sequence is the diagonal rule, which provides the order as:

• 1s
• 2s, 2p
• 3s, 3p, 4s
• 3d, 4p, 5s
• 4d, 5p, 6s
• 4f, 5d, 6p, 7s
• 5f, 6d, 7p

Following this order helps in writing electron configurations step by step for each new element based on the number of electrons present. The systematic filling of these orbitals ensures that the arrangement minimizes the atom's energy, which is the most stable configuration under standard conditions.

Electron Orbitals

Electron orbitals are regions around an atom's nucleus where electrons are most likely to be found. Each orbital can hold a specific number of electrons and is defined by quantum numbers. The main types of orbitals to consider include the s, p, d, and f orbitals, each with distinct shapes and energy levels. Here is a quick overview of their characteristics:

• s orbital: Spherical shape and can hold a maximum of 2 electrons.
• p orbital: Dumbbell-shaped and can accommodate up to 6 electrons across three orientations (x, y, z).
• d orbital: More complex shapes with a capacity for up to 10 electrons in five orientations.
• f orbital: Even more complex, with a maximum of 14 electrons across seven orientations.

Understanding these orbitals is crucial for determining electron configurations, and for predicting chemical behavior and bonding patterns in molecules. The filling of these orbitals follows specific rules, which not only help define the electron configuration of elements like bohrium but also bring to light their similarities and differences with neighboring elements in the periodic table.