Sodium Bohr Model — Diagram and Drawing Instructions

Sodium is a metal with a strong reactivity. It is denoted by the symbol Na and has the atomic number 11. It is an alkali metal because it belongs to group 1A of the periodic chart. It has a silvery-white colour and can be found in nature as minerals such as sodalite, rock salt, and feldspar.

It is a significant ion found in the extracellular fluid of many species, including humans, and serves as an important component. It also aids in the maintenance of numerous vital bodily functions such as osmotic balance, blood pressure, and blood volume.

Most of you aren’t familiar with the sodium Bohr model. In this tutorial, I’ll teach you how to create a Bohr diagram and explain it in a straightforward and straightforward manner.

So, let’s get this party started.

The Sodium Bohr Model

After merging Niel Bohr’s results into the previously given Bohr model, the Bohr-Rutherford model was presented in 1913.

The Bohr model is a visual representation of the atomic structure and all of the atomic components. It depicts the number and location of all of the atomic species within an atom.

To comprehend the Bohr atomic model, we must first comprehend the atomic particles and their significance in the atomic structure. The following are the terminology used in the Bohr atomic model:

• Nucleus: The nucleus is the positively charged body that sits at the heart of the atom. Positively charged protons and neutral neutrons make up the nucleus.

• Protons: The positively charged particles that make up the nucleus of an atom. They are indicated by the sign p+ and were named by Ernst Rutherford.

• Neutrons: Neutrons, like protons, are found in the nucleus and are important for an atom’s stability. They are also in charge of many of the atom’s physical properties. The sign n° is used to represent them.

• Electrons: Electrons are negatively charged particles that orbit the nucleus of an atom. According to the Bohr-Rutherford model, electrons orbit the nucleus in preset circular orbits.

• Shell or orbit: The electrons’ circular route around the nucleus is known as the shell or orbit. These are fixed tracks, and the amount of electrons that can fit into a single shell varies as well.

The shells are named K, L, M, N, and so on, or 1, 2, 3, 4, 5, and so on, with the lowest number indicating the shell closest to the nucleus.

According to the Bohr-Rutherford model, the electrons in the shell nearest to the nucleus have the lowest energy and are known to be in the ground state. After absorbing a particular amount of energy, electrons move to higher orbits.

Valence electrons are electrons that have the most energy and are found in the nucleus’ outermost shell. These electrons are involved in the creation of atom-to-atom bonding.

There are 11 protons, 12 neutrons, and 11 electrons in a sodium atom. Around the nucleus, electrons are dispersed in K, L, and M shells.

Sodium AtomValue
No. of Proton11
No. of Neutron12
Number of Electrons11
Number of shells3
Number of electrons in first (K) shell2
Number of electrons in second (L) shell8
Number of electrons in third (M) shell1
Number of valence electrons1

Drawing the Sodium Bohr Model

Sodium is an alkali metal that belongs to Periodic Table Group 1A:

The sodium box, as illustrated above, contains the following information:

• Sodium has an atomic number of 11.

• Sodium’s electronic configuration is 1s22s22p63s1.

• The chemical symbol for sodium is Na.

• Sodium has an atomic mass of 22.989.

To draw the Bohr model of sodium, we must first determine the total number of atomic particles in the atom.

Let’s start by figuring out how many protons are in a sodium atom.

The number of protons in an atom is always equal to its atomic number.

When it comes to sodium, the atomic number is 11.

As a result, the number of protons in the sodium atom equals the atomic number, which is 11.

Now we’ll figure out how many neutrons are in the nucleus of the sodium atom.

The following is the formula for calculating the number of neutrons in an atom:

Atomic mass (rounded up to the closest full number) – number of protons = number of neutrons

As stated in the sodium box above, the atomic mass of sodium is 22.989.

To reach the nearest whole number, round up this value.

As a result, the atomic mass of sodium can be calculated to be 23.

Now, using the formula above, determine the amount of neutrons:

The number of neutrons in an atom of sodium is 23 – 11 = 12.

We can draw the nucleus of the sodium atom using the previous results because an atom’s nucleus is made up of neutrons and protons.

The symbols p+ and n° in the diagram above represent positively charged protons and neutral neutrons, respectively.

We’ll now figure out how many electrons there are in the sodium atom.

The atomic number of atoms is also equivalent to the amount of electrons.

As a result, the number of electrons in a sodium atom equals the atomic number, which is 11.

This means that 11 electrons circulate around the nucleus of a sodium atom. These electrons must now be accommodated around the nucleus.

The following formula gives the maximum number of electrons that can be permitted in each shell:

2n2 is the maximum number of electrons in a shell.

n is the number of shells in this case.

Calculating the number of electrons in the first shell of the sodium atom, the K shell:

Number of electrons in the sodium atom’s K shell = 2n2 = 2 (1)2 = 2

In the K shell, two electrons can thus be accommodated. It can be represented as follows after attaching the K shell to the nucleus of the sodium atom:

Shell of Sodium K

We’ll now determine the number of electrons in the sodium atom’s second shell, the L shell.

2n2 = 2 (2)2 = 8 maximum number of electrons in the L shell of a sodium atom

In the L shell of the sodium atom, 8 electrons can thus be accommodated.

However, in any shell with more than two electrons (except the K shell), the first four electrons are added in a clockwise direction at 90° to each other.

Following that, the remaining electrons are added in a group of four in a clockwise pattern, with the angle between the electrons decreasing with each addition.

So, let’s add the first four electrons to the sodium atom’s L shell, and it looks like this:

We’ll now add the remaining four electrons to the K shell, this time clockwise but at a less than 90° angle.

As a result, the sodium atom now appears as follows:

Shell Sodium L

After that, we’re left with one final electron, which will now be housed in the M shell.

2n2 = 2 (3)2 = 18 maximum number of electrons in M shell of sodium atom

After adding all 11 electrons to the nucleus of the sodium atom, the following diagram can be drawn:

Model of Sodium Bohr

As a result, the final Bohr model of the sodium atom has 12 neutrons and 11 protons in the nucleus, while 12 electrons orbit around it, with 2 electrons in the K shell, 8 electrons in the L shell, and 1 electron in the M shell.

I’ve included a video to demonstrate what I’m talking about. Take a peek around.

Associated Topics

Model of Boron Bohr

Sodium’s Lewis Structure is Deduced

The Lewis structure of an atom is a graphical representation of the nucleus’s valence electrons.

The atomic symbol of the atom is used to indicate the nucleus, while the dots around the nucleus represent electrons. An electron dot diagram is another name for this.

The sodium atom has one valence electron, as seen in the previous section. As a result, sodium’s electron dot structure is as follows:

Wikimedia Commons – Lewis dot Na.svg

Most Commonly Asked Questions (FAQs)

Answer: While not entirely right, the Bohr model correctly defines several atom features.

What’s the problem with Bohr’s model?


It also ignores the subshells, such as s, p, d, f, and so on, when discussing electron housing.

Sodium’s Properties

The following are some of sodium’s most important properties:

• Sodium hydroxide and hydrogen are formed when sodium reacts with water.

• It also interacts with metal halides, forming metals and sodium chloride as a result.

• Sodium has a boiling temperature of 883 degrees Celsius and a melting point of 97.5 degrees Celsius, respectively.

• At 20 °C, sodium has a density of 0.97 gm/cm3.

• On the Pauling scale, sodium has an electronegativity of 0.9.


The sodium atom has 11 protons, 11 electrons, and 12 neutrons, according to the Bohr model.

The presence of protons and neutrons inside the nucleus of the atom gives it a positive charge.

The electrons are said to rotate around the nucleus in a specific route. Orbits or shells are the names given to these circular pathways.

The atomic number of an atom is always the same as the number of protons and electrons in the atom.

The formula for calculating the number of neutrons in an atom is:

Atomic mass (rounded up to the closest full number) – number of protons = number of neutrons

The electrons in the sodium atom are organised into three shells: K, L, and M, each having 2, 8, or 1 electron.

The formula 2n2 gives the maximum number of electrons that can be accommodated in a shell.

Read more: Is IF5 a Polar or a Nonpolar Protein?

Misha Khatri
Misha Khatri is an emeritus professor in the University of Notre Dame's Department of Chemistry and Biochemistry. He graduated from Northern Illinois University with a BSc in Chemistry and Mathematics and a PhD in Physical Analytical Chemistry from the University of Utah.


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