Aluminum(Al) is the 13th element in the periodic table and its symbol is ‘Al’. The electron configuration of aluminum and the orbital diagram is the main topic of this article. Also, valency and valence electrons of aluminum, various reactions, and compound formation, bond formation have been discussed. Hopefully, after reading this article you will know in detail about this.
The total number of electrons in aluminum is thirteen. These electrons are arranged according to specific rules of different orbits. The arrangement of electrons in different orbits and orbitals of an atom in a certain order is called electron configuration. The electron configuration of aluminum(Al) atoms can be done in two ways.
- Electron configuration through orbit
- Electron configuration through orbital
Electron configuration through orbitals follows different principles. For example Aufbau principle, Hund’s principle, Pauli’s exclusion principle. There is an article published on this site detailing the electron configuration, you can read it if you want.
Aluminum(Al) electron configuration through orbit
Scientist Niels Bohr was the first to give an idea of the atom’s orbit. He provided a model of the atom in 1913. The complete idea of the orbit is given there. The electrons of the atom revolve around the nucleus in a certain circular path. These circular paths are called orbit(shell). These orbits are expressed by n. [n = 1,2,3,4 . . . The serial number of the orbit]
K is the name of the first orbit, L is the second, M is the third, N is the name of the fourth orbit. The electron holding capacity of each orbit is 2n2.
- n = 1 for K orbit.
The electron holding capacity of K orbit is 2n2 = 2 × 12 = 2 electrons.
- For L orbit, n = 2.
The electron holding capacity of the L orbit is 2n2 = 2 × 22 = 8 electrons.
- n=3 for M orbit.
The maximum electron holding capacity in M orbit is 2n2 = 2 × 32 = 18 electrons.
- n=4 for N orbit.
The maximum electron holding capacity in N orbit is 2n2 = 2 × 42 = 32 electrons.
Therefore, the maximum electron holding capacity in the first shell is two, the second shell is eight and the 3rd shell can have a maximum of eighteen electrons. The atomic number is the number of electrons in that element. The atomic number of aluminum(Al) is 13. That is, the number of electrons in aluminum is thirteen. Therefore, the aluminum atom will have two electrons in the first shell, eight in the 2nd orbit, and three electrons in the 3rd shell. Therefore, the order of the number of electrons in each shell of an aluminum atom is 2, 8, 3.
Electrons can be arranged correctly through orbits from elements 1 to 18. The electron configuration of an element with an atomic number greater than 18 cannot be properly determined according to the Bohr atomic model. The electron configuration of all the elements can be done through orbital diagrams.
Electron configuration of aluminum(Al) through orbital
The German physicist Aufbau first proposed an idea of electron configuration through sub-orbits. The Aufbau method is to do electron configuration through the sub-energy level. These sub-orbitals are expressed by ‘l’.
The Aufbau principle is that the electrons present in the atom will first complete the lowest energy orbital and then gradually continue to complete the higher energy orbital. These orbitals are named s, p, d, f. The electron holding capacity of these orbitals is s = 2, p = 6, d = 10 and f = 14. The Aufbau electron configuration method is 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p 7s 5f 6d.
The first two electrons of aluminum enter the 1s orbital. The s-orbital can have a maximum of two electrons. Therefore, the next two electrons enter the 2s orbital. The p-orbital can have a maximum of six electrons. So, the next six electrons enter the 2p orbital.
The second orbit is now full. So, the remaining electrons will enter the third orbit. Then two electrons will enter the 3s orbital of the third orbit and the remaining 1 electron will be in the 3p orbital. Therefore, the aluminum(Al) electron configuration will be 1s2 2s2 2p6 3s2 3p1.
How to write the orbital diagram for aluminum(Al)?
To create an orbital diagram of an atom, you first need to know Hund’s principle and Pauli’s exclusion principle. Hund’s principle is that electrons in different orbitals with the same energy would be positioned in such a way that they could be in the unpaired state of maximum number and the spin of the unpaired electrons will be one-way. And Pauli’s exclusion principle is that the value of four quantum numbers of two electrons in an atom cannot be the same. To write the orbital diagram of aluminum, you have to do the electron configuration of aluminum. Which has been discussed in detail above.
1s is the closest and lowest energy orbital to the nucleus. Therefore, the electron will first enter the 1s orbital. The first electron will enter in the clockwise direction and the next electron will enter the 1s orbital in the anti-clockwise direction. The 1s orbital is now filled with two electrons. The next two electrons will enter the 2s orbital just like the 1s orbital.
The next three electrons will enter the 2p orbital in the clockwise direction and the next three electrons will enter the 2p orbital in the anti-clockwise direction. The next two electrons will enter the 3s orbital and the remaining one electron will enter the 3p orbital in a clockwise direction. This is clearly shown in the figure of the orbital diagram of aluminum.
Electron configuration of aluminum ion(Al3+)
Ground state electron configuration of aluminum is 1s2 2s2 2p6 3s2 3p1. After the electron configuration, the last shell of the aluminum atom has three electrons. In this case, the valency and valence electrons of aluminum are 3. The elements that have 1, 2, or 3 electrons in the last shell donate the electrons in the last shell during bond formation. Aluminum donates the electron of the last shell to form bonds and turns into an aluminum ion(Al3+). The elements that form bonds by donating electrons are called cations. That is, aluminum is a cation element.
Al – 3e– → Al3+
The electron configuration of aluminum ions(Al3+) is 1s2 2s2 2p6.
How do you write the electron configuration for aluminum(Al)?
Ans: Aluminum(Al) electron configuration is 1s22s22p63s2 3p1.
How many electrons does aluminum(Al) have?
Ans: 13 electrons.
How many valence electrons does aluminum(Al) have?
Ans: Three valence electrons.
What is the symbol for aluminum(Al)?
Ans: The symbol for aluminum is ‘Al’.