SO3 means Sulfur Trioxide. This is among the most pollutant chemical compounds in the gaseous form. That is additionally a main agent in the acid rain. The main use of this ingredient is to make sulfuric acid for industrial purposes.

You are watching: What is the angle between the sulfur-oxygen bonds in the sulfur trioxide ( so3 ) molecule?

SO3 which is additionally spelled together Sulphur Trioxide sometimes, is a trigonal planar molecule the is non-flammable. In this article, ns will provide you some information regarding SO3 molecule geometry v the explanations that Lewis structure, polarity, and also hybridization.

Sulfur Trioxide molecular Geometry

Being an intelligent and well-practiced person being, you must recognize what is molecular geometry, however let me review it for the all young students the end there. Molecule geometry is the three-dimensional framework of the atom which help in the structure of a molecule. It have the right to determine reactivity, polarity, color, attraction, biological activity, etc.

SO3 includes two components mainly – Sulfur and Oxygen. There are one sulfur atom and also three oxygen atom which are spread out as much away together they can! atoms of oxygen room surrounded by electrons. This electrons are an adverse and repel each other.

You can additionally remember it by AXN. Where;

A means Sulfur, which is main atomX means No. Of atom bonded with main sulfur

In this formula that SO3, us don’t have any type of non-bonding electron, and also that is why we don’t bother about N. Moreover, together there room three oxygen, it will be X3.

That method we have AX3 because that the SO3 molecule. (By the way, that is the reason why SO3 is having the shape of Trigonal Planar.) The bond angle of SO3 is 120 degrees.

Lewis structure of SO3

Valence: Here, sulfur in the center since of its lowest electron capability, and also three oxygen approximately it. Sulfur bring 6, and also oxygen bring 3 each. That means; SO3 has 24 valence electrons. 6 + (3 x 6) = 24.

Now have actually a watch of Lewis framework again;


When we draw it, firstly we obtain the three frameworks at the top. Sulfur in the center and Oxygen approximately it is make a connection (each) to the main atom. There should be single bonds initially.

There are 6 electron in the framework which we have actually made, and also there room 24 in total. Therefore we need to put 18 electrons down. Now fill the external atoms so that it satisfies the octet rule.

It looks like this;


Tip: once you placed them, begin counting native 7 come 24.

Then take it a decision regarding the officially charge. Formal fee helps friend to number out which atoms don’t need electrons.

It’s the no. Of electrons that the atom carried (For example, the oxygen bring 6) minus the no. Of electrons which room alone that is the lone pairs about the atom minus half the number of electrons in bonds.

If you desire to find out, usage this formula to make it simple;

Formula: Valence electrons – Dots – No. Of lines = ‘?’

If we talk about Sulfur, there will be 6 – 0 – 3 = +3.

Here in this case, because that oxygen, we have 6 (oxygen) – 6 (dots) – 1 (bonds) = –1.

So, –1 native the other 2 oxygen because all are the same!

The sulfur can handle 12 electrons every atom. Now, take out 2 dots from each of the oxygen and also put one much more bond link to each.

Now, it will certainly look favor this;


So, together you deserve to see, now there space 10 electrons about it. Sulfur violate the octet rule. And also the reason is that all officially charges become 0. So, if girlfriend recalculate the things, at last, it will certainly be favor 6 – 0 – 6 = 0. I hope you guys are clear about the Lewis framework of SO3. Now, let’s talk about polarity.

Polarity the SO3

Many students have the concern – Is SO3 polar or nonpolar? several of the professionals also have the very same confusion. Here is the price in the easiest explanation…


In this formula, all atoms that oxygen space symmetrical. They all are having actually the same variety of bonds and also lone pair electrons. Now if we use a model called the VSEPR, (Valence shell Electron-Pair Repulsion – a version which is based on the repulsive actions of electron pairs) we will uncover out that as all oxygen space spread out, they repel every other, which intend SO3 as nonpolar.

So from now onwards, once someone will ask girlfriend a question choose – is SO3 polar? friend should give answer confidently, NO that is not due to the fact that they carry out not have any an adverse or confident signs. That is trigonal planar with symmetric charge distribution on the central atom.

SO3 Hybridization

As you deserve to see in the structure; between each atom, we have dual bonds. One is a sigma bond (σ), and the various other one is the pi bond (π). To discover out SO3 Hybridization, us should uncover the steric number. The formula the steric number is the addition of the number of atoms bonded and also lone bag of electrons.

See more: The Sum Of Two Numbers Is 40 . One Number Is 4 Times As Large As The Other. What Are The Numbers?

There space 3 sigma binding which typical we have actually three regions. One sigma bond and also two pairs of unbonded electrons. That means we have an S and also two p orbitals to be hybridized. In this case, the steric number is 3, therefore the hybridization that SO3 is SP2.

That’s it!!! This is the simplest explanation of SO3 electron geometry. I hope this article will be beneficial for friend whenever you need any type of guidance or assist to deal with your confusions concerning the molecular geometry that SO3. In ~ last, I simply want come say – never stop learning, since curiosity is the vital to success. All the really best!