# How many empty orbitals?

I know there's 1s, 2s, 2p, 3s, 3p, 4s, 3d, etc. From my understanding, each of those is an orbital. So for example, carbon has 3 orbitals (1s-2, 2s-2, 3p-2). Is that right?

If it is, now I have a question about EMPTY orbitals- I don't understand this at all. For example, take carbon. Well carbon has 6 electrons and it would be: 1s-2, 2s-2, 2p-2. The p ones have 3 suborbitals, so carbon has one empty SUB-orbital?? But how does any element have an empty orbital? Isn't their outermost orbital the one that has at least one valence electron in it (i.e it's not empty)?

• zillions of empty orbitals. Look at the spectral series for hydrogen. en.wikipedia.org/wiki/Hydrogen_spectral_series – MaxW Sep 28 '16 at 1:22
• So the orbital is not empty, but one of its suborbitals is empty. What is your question? – DHMO Sep 28 '16 at 9:45
• I don't think this question deserves the downvotes. The person simply had an issue of nomenclature [suborbitals is the incorrect term (or atleast quite uncommon) while orbitals is the correct term for what he had in mind]. – FreezingFire Sep 28 '16 at 19:18
• There is 1 ns orbital, n=1,2,.. There are 3 np orbitals, n=2,3,... There are 5 nd orbitals, n=3,4,... There are 7 nf orbitals, n=4,5,... Electrons in multiple p,d,f, orbitals differe in their orbital angular momentum. – Poutnik Sep 6 at 7:01

The orbitals are: $$\large 1s,\; 2s,\; 2p_x,\; 2p_y,\; 2p_z,\; 3s,\; 3p_x,\; 3p_y,\; 3p_z,\; 3d_{xy},\; 3d_{yz},\; 3d_{zx},\; 3d_{x^2-y^2},\; 3d_{z^2}\; ...$$ In your example, the electronic configuration of carbon is: $$\ce{_6^{12}C}=1s^2 \; 2s^2 \; 2p_x^1 \; 2p_y^1 \; 2p_z^0$$ My point is, the classification is like this: there are four (commonly occuring) types of orbitals, the s-orbitals, the p-orbitals, the d-orbitals and the f-orbitals. The first shell consists of only the $1s$ orbital. The second shell consists of the $2s$ orbital and the three $2p$ orbitals: $2p_x, 2p_y, 2p_z$. Similarly $3d$ is just the blanket name for the five different $3d$ orbitals as mentioned above.

Thus in carbon, the $2p_z$ orbital is empty, and the $2p_x$ and $2p_y$ orbitals are half filled (holding one electron). Actually, you could equivalently left the $2p_x$ or $2p_y$ orbital empty, it doesn't matter.

You may be confused with the naming system of the separate orbitals ("what is this $2p_x$ and $3d_{xy}$ and $3d_{x^2-y^2}$ this guy is talking about?"). Well, they are just names given to the separate $p$ and $d$ orbitals, based on their mathematical nature. (See atomic orbitals on Wikipedia).

• Thank you. What then is a suborbital? I thought the 2px, 2py, 2pz were the 3 suborbitals of the p orbital. – heyimaperson Sep 28 '16 at 18:25
• I am hearing the word suborbitals for the first time really...it is not in common use! Ideally you should use the word orbitals (specifically, atomic orbitals) as it is referred to in the Wikipedia page, unless your syllabus demands that specific word. – FreezingFire Sep 28 '16 at 19:04

An orbital is a region of space where an electron may occupy, usually we draw a hard boundary at where the electron exist 90% of the time but it actually extends to infinity (ie. an electron can be anywhere in the universe).

Naming. In an atom, there’s principal quantum shell, sub-shell, then orbitals. “Suborbitals” do not exist. For example, in the second principal quantum shell $$n = 2$$, there are one $$2s$$ and one $$2p$$ sub-shell. The $$2p$$ subshell is made out of 3 $$p$$ orbitals: the $$2p_x$$, $$2p_y$$ and $$2p_z$$ orbitals, where each orbital can hold a maximum of 2 electrons.

In carbon, one of the $$p$$ orbitals is empty. What does it mean? It means that this orbital is the region of space an electron will occupy if there is an electron. It’s just a region of space.

• I feel compelled to mention that for the advanced reader, even this is not quite correct: an orbital is not a region of space, but rather a single-electron wavefunction, which forms part of the overall, multi-electron, wavefunction (to a certain approximation). This makes it difficult to ascribe physical meaning to an empty orbital as you do in the final paragraph: if you were to add an electron to a carbon atom, the Hamiltonian would be different, and consequently the extra orbital required will not be exactly the same as the vacant orbital in the carbon atom. – orthocresol Sep 1 at 23:14
• ... and I do not mean to say that this is a bad answer in any respect: it is just that this description of an orbital will only work up to a point in one's chemistry education, hence my addition of a disclaimer. – orthocresol Sep 1 at 23:18
• I agree! Thanks for the clarification – Kiewriosity Sep 3 at 0:05