What is the Charge on HSO4 (Hydrogen Sulfate ion)? And Why?

The Charge of HSO4 is 1-.

But the question is how can you find the charge on HSO4 (hydrogen sulfate ion)?

Well there are 2 methods by which you can find the charge of HSO4.

Lets dive right into these methods one by one.

If you are a visual learner like me, then here is a short two minute video for you.

Method 1: By looking at what it is bonded to

The charge of HSO4 (hydrogen sulfate ion) can be found out by looking at what it is bonded to.

So let’s take some examples of compounds that contain HSO₄; like NaHSO₄, KHSO₄, etc.

Example 1: NaHSO₄
In NaHSO₄, the HSO₄ is bonded to Sodium (Na).
You know that the ionic charge of Na is 1+.
So you can easily say that the charge of HSO₄ should be 1-, then only it will get canceled out.
Hence the charge of HSO₄ in NaHSO₄ is 1-.

Example 2: KHSO₄
In KHSO₄, the HSO₄ is bonded to Potassium (K).
And again, you know that the ionic charge of K is 1+.
So here also you can easily say that the charge of HSO₄ should be 1-, then only it will get canceled out.
Hence the charge of HSO₄ in KHSO₄ is 1-.

As seen from the above examples,
The charge of HSO₄ is 1-.

In this way, you can easily find the charge of HSO4 by looking at what it is bonded to.

Method 2: By calculating the formal charge using lewis structure

In order to calculate the formal charge on HSO4 (hydrogen sulfate ion), you should know the Lewis dot structure of HSO4 (hydrogen sulfate ion).

Here is the lewis structure of HSO4.

Now using the above lewis structure of HSO4, you have to find the formal charge on each atom that is present in the HSO4 molecule.

For calculating the formal charge, you need to remember this formula;

Formal charge = Valence electrons – Nonbonding electrons – (Bonding electrons)/2

You can see the bonding and nonbonding electrons of HSO4 from the image given below.

So now let’s calculate the formal charge on each individual atom present in HSO4.

Formal charge on Hydrogen atom:
Valence electron = 1 (as it is in group 1 on periodic table) ^[1]
Nonbonding electrons = 0
Bonding electrons = 2

So according to the formula of formal charge, you will get;

Formal charge on Hydrogen = Valence electrons – Nonbonding electrons – (Bonding electrons)/2 = 1 – 0 – (2/2) = 0

So the formal charge on hydrogen atom is 0.

Formal charge on Sulfur atom:
Valence electron = 6 (as it is in group 16 on periodic table) ^[2]
Nonbonding electrons = 0
Bonding electrons = 12

So according to the formula of formal charge, you will get;

Formal charge on Sulfur = Valence electrons – Nonbonding electrons – (Bonding electrons)/2 = 6 – 0 – (12/2) = 0

So the formal charge on sulfur atom is 0.

Formal charge on double bonded Oxygen atom:
Valence electron = 6 (as it is in group 16 on periodic table) ^[3]
Nonbonding electrons = 4
Bonding electrons = 4

So according to the formula of formal charge, you will get;

Formal charge on double bonded Oxygen = Valence electrons – Nonbonding electrons – (Bonding electrons)/2 = 6 – 4 – (4/2) = 0

So the formal charge on double bonded oxygen atom is 0.

Formal charge on single bonded Oxygen atom:
Valence electron = 6 (as it is in group 16 on periodic table)
Nonbonding electrons = 6
Bonding electrons = 2

So according to the formula of formal charge, you will get;

Formal charge on single bonded Oxygen = Valence electrons – Nonbonding electrons – (Bonding electrons)/2 = 6 – 6 – (2/2) = 1-

So the formal charge on single bonded oxygen atom is 1-.

Now let’s put all these charges on the lewis dot structure of HSO4.

So there is overall 1- charge left on the entire molecule.

This indicates that the HSO4 (hydrogen sulfate ion) has 1- charge.

I hope you have understood the above calculations of HSO4 (hydrogen sulfate ion). But for your tests, you don’t need to remember the entire calculations. You should just try to remember that HSO4 has 1- charge.

Check out some other related topics for your practice.

Related topics:
Charge on Methane (CH4)
Charge of Antimony (Sb)
Charge of Molybdenum (Mo)
Charge on HCN
Charge on N2O (Nitrous oxide)