Phosphorus Valence Electrons

This electron must go into the lowest-energy subshell available, the 3 s orbital, giving a 1 s 2 2 s 2 2 p 6 3 s 1 configuration. Locate the nearest noble gas preceding phosphorus in the periodic table. Then subtract its number of electrons from those in phosphorus to obtain the number of valence electrons in phosphorus. Both nitrogen and phosphorus have 5 valence electrons, but nitrogen has valency of 3 while phosphorus has valency of 3 or 5. Maybe phosphorus can gain 3 electrons or remove 5 electrons.But is it possible to remove 5 electrons? Or is it that phosphorus valence shell is farther away than nitrogen, so it is easier for phosphorus to.

P Valence Electrons
Phosphorus Valence Electrons Charge
Phosphorus Valence Electrons Diagram
Phosphorus Valence Electrons And Ion

A step-by-step description of how to write the electron configuration for Phosphorus (P). In order to write the P electron configuration we first need to kn.

Lewis structure of phosphate ion is drawn clearly in this tutorial step by step. Total valence electrons concept is used to draw the lewis structure of PO₄^3- ion. In lewis structure, there should be charges on atoms.

Phosphate ion | PO₄^3-

Phosphate ion is one of the oxyanion of phosphorous. Phosphorous is at +5 oxidation state in PO₄^3-. Also, phosphate ion has a -3 charge.

Lewis structure of PO₄^3- ion

In the lewis structure of PO₄^3-, three is a double bond between phosphorous atom and one oxygen atom. Between other oxygen atoms, there are only single bonds with phosphorous atom. Also, each oxygen atom has a -1 charge.

Related lewis structures to H₃PO₄

H₃PO₂ lewis structure
H₃PO₃ lewis structure

Steps of drawing lewis structure of PO₄^3-

Following steps are required to draw the PO₄^3- lewis structure and they are explained in detail in this tutorial.

Find total number of electrons of the valance shells of sulfur and oxygen atoms
Total electrons pairs
Center atom selection
Put lone pairs on atoms
Check the stability and minimize charges on atoms by converting lone pairs to bonds.

Drawing correct lewis structure is important to draw PO₄^3- resonance structures correctly.

Total number of electrons of the valance shells of SO₄^2-

Phosphorous is located at 5^th group in the periodic table. Therefore phosphorous has five valence electrons in its last shell. Oxygen atom is located at sixth group in the periodic table and has six valence electrons in its last shell.

Total valence electrons given by phosphorous atom = 5

There are four oxygen atoms in PO₄^3- ion, Therefore

Total valence electrons given by oxygen atoms = 6 *4 = 24

There are -3 charge on PO₄^3- ion. Therefore there are three more electrons which comes from outside to contribute to the total valence electrons.

Total valence electrons = 5 + 24 + 3 = 32

Total valence electrons pairs

Total valance electrons pairs = σ bonds + π bonds + lone pairs at valence shells

Total electron pairs are determined by dividing the number total valence electrons by two. For, PO₄^3- ion, Total pairs of electrons are 16.

Center atom of PO₄^3- ion

To be the center atom, ability of having greater valance is important. Therefore sulfur has the more chance to be the center atom (See the figure) because sulfur can show valance of 6. Maximum valence of oxygen is two. So, now we can build a sketch of PO₄^3- ion.

Mark electrons as lone pairs on atoms

There are already four P-O bonds around the phosphorous atom in the above sketch. Therefore only twelve (16-4 = 12) valence electrons pairs are remaining to draw the lewis structure.
First, mark those twelve valence electrons pairs as lone pairs on outside atoms (on oxygen atoms). One oxygen atom will take three lone pairs following the octal rule (oxygen atom cannot keep more than eight electrons in its valence shell).
For four oxygen atoms, twelve electrons pairs are spent. Now all electron pairs are spent. There is no electron pairs to mark on phosphorous atom.

Charges on atoms

After, marking electron pairs on atoms, we should mark charges of each atom. Each oxygen atom will get a -1 charge and phosphorous atom get a +1 charge. The overall charge of ion is ( -1*4 + (+1) ) = -3.

Check the stability and minimize charges on atoms by converting lone pairs to bonds

When charges exist everywhere (on atoms) in a ion or a molecule, that structure is not stable. We should try to reduce charges on atoms as much as possible. Now, we are going to learn how to reduce charges of atoms in sulfate ion.

Oxygen atoms should hold negative charges because electronegativity (3.5) of oxygen is higher than phosphorous (2.1). Otherwise, we can say, ability of holding negative charges is great in oxygen atoms than phosphorous atoms.
The drawn structure is not a stable one because all atoms have charges.
Now, we should try to minimize charges by converting lone pair or pairs to bonds. So convert one lone pair of one oxygen atom to make a new P-O bond.
Now there is a double bond between phosphorous atom and one oxygen atom (one P=O bond). Now, there are three P-O single bonds between phosphorous atom and other three oxygen atoms (three P-O bonds).

You see charges of atoms in PO₄^3- are reduced. Now, there is no charge in one oxygen atom and phosphorous atom. So we have an stable ion than previous one.

Lewis structure of PO₄^3-

Can I reduce charges of atoms furthermore ?

You should know, phosphorous can keep more than eight electrons in its last shell. Therefore we can convert one more lone pair of another oxygen atom to a bond.

But, when you try to do this, phosphorous will get a -1 charge. Earlier in this tutorial, I told you that, most electronegative element should have the negative charges. Therefore, we cannot reduce charges furthermore.

Questions

How many oxygen atoms have charges in PO₄^3- lewis structure?

Three oxygen atoms have charges. One oxygen atom holds - 1 charge and overall there is -3 charge.

In phosphate ion lewis structure, there is -3 charge. Are their charge and lone pairs on phosphorous atom?

There are no any charge on phosphorous atom in phosphate ion lewis structure. Also, there is no lone pair or pairs in phosphate ion lewis structure.

How do I get the lewis structure of H₃PO₄ from PO₄^3- ?

Three hydrogen atoms are linked to oxygen atoms of PO₄^3- in H₃PO₄ molecule. There were -1 negative charge on each of oxygen atom and they will be lost due to joining with hydrogen atoms.

Why phosphorous atom will not take a hydrogen atom to make a P-H bond?

If a hydrogen atom is joint to the phosphorous atom, phosphours atom will get a minus charge which is not acceptable because phosphorous has a lower electronegativity than oxygen.

Are there lone pairs on phosphorus atom in phosphate Lewis structure?

Around phosphorus atom, three single bonds and one double bond exist. No lone pairs exist on phosphorus atom. Also, no charge exists on phosphorus atom in Lewis structure of PO₄^3-

SO₃^2- lewis structure and resonance structures NO₃^- lewis structure NO₃^- resonance structuresNO₂^- lewis structureN₂O lewis structure, resonance structures N₂O₅ resonance structuresResonance structures examplesH₃PO₄ lewis structure

Answer: A neutral Phosphorus Atom has five valence electrons. These are contained in the third energy level of the atom.

The Phosphorus Element as it would be represented on a modern periodic table. Source

Phosphorus is an element which is part of Group 15 (formally known as the Pnictogen group) and is directly below the nitrogen atom. As was mentioned before, a neutral Phosphorus Atom contains five valence electrons in the third shell. You can see a Bohr Model of Phosphorus below this paragraph. It also supports the original answer of five valence electrons.

Bohr Model of a Phosphorus Atom.

Due to the number of valence electrons, Phosphorus is capable of forming three bonds with other elements. Yet since it has a third-energy level, it can form more than three bonds if it is favorable to do so. Phosphorus tends to form an anion even though it has a low electronegativity. Due to its high reactivity, phosphorus is never found a pure element on earth.

P Valence Electrons

Electron Configuration of Phosphorus with a Lewis Diagram on the side as well. Source

The Valence Electrons are found in different types of orbitals. Two are in the s-orbital (a circular orbital) while the other 3 are in p-orbitals (bell-shaped orbitals). There are a total of 4 orbitals in the valence shell to minimize electron-electron repulsion. Since their is less electron-electron repulsion, this formation is actually more stable than one with an extra electron. Therefore Phosphorus has a higher ionization than its Group-16 (Chalcogen) neighbors Sulfur.

Phosphorus as it moves in a biochemical process. Source

Phosphorus is necessary for some functions in life and is an essential component of fertile soil. It moves as a compound (not as a pure element) through what is called the Phosphorus cycle from the soil to plants and then back into the air before returning to the soil. Phosphorus is also essential component of matches. It was discovered in 1669 by Hening Brand.