# Molybdenum orbital diagram

The orbital diagram of molybdenum shows that the 1s subshell has 2 electrons, the 2s subshell has 2 electrons, the 2p subshell has 6 electrons, the 3s subshell has 2 electrons, the 3p subshell has 6 electrons, the 4s subshell has 2 electrons, the 3d subshell has 10 electrons, the 4p subshell has 6 electrons, the 5s subshell has 1 electron, and the 4d subshell has 5 electrons.

Contents

## Steps

Here’s how you can draw the orbital diagram of molybdenum step by step.

#1 Find electrons of molybdenum
#2 Write electron configuration of molybdenum
#3 Draw orbital diagram of molybdenum

Let’s break down each step in detail.

### Find electrons

The atomic number of molybdenum represents the total number of electrons of molybdenum. Since the atomic number of molybdenum is 42, the total electrons of molybdenum are 42.

### Write electron configuration

The electron configuration of molybdenum is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d5.

Now in the next step, start drawing the orbital diagram for molybdenum.

### Draw orbital diagram

Before drawing the orbital diagram, you should know the three general rules.

• Aufbau principle – electrons are first filled in lowest energy orbital and then in higher energy orbital
• Pauli exclusion principle – two electrons with the same spin can not occupy the same orbital
• Hund’s rule – each orbital should be first filled with one electron before being paired with a second electron

Also, you should know the number of orbitals in each subshell.

We can calculate the number of orbitals in each subshell using the formula: 2ℓ + 1

Where, ℓ = azimuthal quantum number of the subshell

For s subshell, ℓ = 0
For p subshell, ℓ = 1
For d subshell, ℓ = 2
For f subshell, ℓ = 3

So each s subshell has one orbital, each p subshell has three orbitals, each d subshell has five orbitals, and each f subshell has seven orbitals.

Now start to draw!

As mentioned above, the electron configuration of molybdenum is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d5. Hence, draw the blank orbital diagram of molybdenum up to 4d subshell as follows:

In the above orbital diagram, the box represents an orbital. Each orbital has a capacity of two electrons. And the arrows (↑↓) are drawn inside the box to represent electrons.

Now 1s2 indicates that the 1s subshell has 2 electrons. So draw two arrows in the 1s box showing two electrons as follows:

2s2 indicates that the 2s subshell has 2 electrons. So draw two arrows in the 2s box showing two electrons as follows:

2p6 indicates that the 2p subshell has 6 electrons. So draw six arrows in the 2p box showing six electrons as follows:

3s2 indicates that the 3s subshell has 2 electrons. So draw two arrows in the 3s box showing two electrons as follows:

3p6 indicates that the 3p subshell has 6 electrons. So draw six arrows in the 3p box showing six electrons as follows:

4s2 indicates that the 4s subshell has 2 electrons. So draw two arrows in the 4s box showing two electrons as follows:

3d10 indicates that the 3d subshell has 10 electrons. So draw ten arrows in the 3d box showing ten electrons as follows:

4p6 indicates that the 4p subshell has 6 electrons. So draw six arrows in the 4p box showing six electrons as follows:

5s1 indicates that the 5s subshell has 1 electron. So draw one arrow in the 5s box showing one electron as follows:

4d5 indicates that the 4d subshell has 5 electrons. So draw five arrows in the 4d box showing five electrons as follows:

That’s it! This is the final orbital diagram of molybdenum as we have used all 42 electrons.

Question: Why does the 5s subshell have only one electron (instead of two electrons), and the 4d subshell has five electrons (instead of four electrons)?

Answer: A half-full 4d subshell is more stable than a partially filled 4d subshell. That’s why the 4d subshell has five electrons (instead of four electrons). And the 5s subshell has one electron (instead of two electrons).