Draw the orbital diagram and write the electron configuration for Selenium and use it to identify the 17th, 23rd and 33rd electrons.

Draw the orbital diagram and write the electron configuration for Selenium and use it to identify the 17th, 23rd and 33rd electrons. Make a table and write the four quantum numbers for each or these electrons using the table.

The Correct Answer and Explanation is:

Of course. Here is the detailed solution for the electron configuration, orbital diagram, and quantum numbers for Selenium.

Selenium (Se) is element number 34 on the periodic table, meaning a neutral atom has 34 electrons. To solve this problem, we will first determine its electron structure and then identify the quantum numbers for the specified electrons.

Electron Configuration and Orbital Diagram

We will fill the atomic orbitals according to the Aufbau principle, which dictates the order of filling based on increasing energy levels.

Electron Configuration for Selenium (Se):

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁴

Orbital Diagram for Selenium (Se):

The diagram visually represents the electron configuration, showing the distribution of electrons within the orbitals. Arrows indicate electrons, with their direction representing spin. We apply Hund’s rule, which states that electrons will singly occupy each orbital in a subshell before any orbital is doubly occupied.

1s: [↑↓]
2s: [↑↓]
2p: [↑↓] [↑↓] [↑↓]
3s: [↑↓]
3p: [↑↓] [↑↓] [↑↓]
4s: [↑↓]
3d: [↑↓] [↑↓] [↑↓] [↑↓] [↑↓]
4p: [↑↓] [ ↑ ] [ ↑ ]

Identifying Specific Electrons

To find the quantum numbers for the 17th, 23rd, and 33rd electrons, we count through the orbital diagram in the order of filling:

• 17th Electron: The first 12 electrons fill the 1s, 2s, 2p, and 3s subshells. The 3p subshell holds electrons 13 through 18. Following Hund’s rule, the 13th, 14th, and 15th electrons are spin-up in each of the three p-orbitals. The 16th electron pairs with the first p-orbital (m_l = -1). Therefore, the 17th electron is the spin-down electron that pairs in the second p-orbital (m_l = 0) of the 3p subshell.
• 23rd Electron: The first 20 electrons fill up to the 4s subshell. The 3d subshell holds electrons 21 through 30. Following Hund’s rule, the first five electrons (21st to 25th) will be spin-up in each of the five d-orbitals. The 23rd electron is the third spin-up electron, located in the third d-orbital (m_l = 0) of the 3d subshell.
• 33rd Electron: The first 30 electrons fill up to the 3d subshell. The 4p subshell holds the final four electrons. The 31st, 32nd, and 33rd electrons will be spin-up in each of the three p-orbitals. The 33rd electron is the third spin-up electron, located in the third p-orbital (m_l = +1) of the 4p subshell.

Quantum Numbers Table

The four quantum numbers describe the state of an electron:

• n (Principal Quantum Number): Energy level or shell.
• l (Azimuthal Quantum Number): Subshell shape (0=s, 1=p, 2=d).
• m_l (Magnetic Quantum Number): Orbital orientation in space (-l to +l).
• m_s (Spin Quantum Number): Electron spin (+1/2 for up, -1/2 for down).

Here is the table summarizing the quantum numbers for the identified electrons: