What is the shape of so2 in the Lewis dot structure?

Skip to the bottom of the message for the answer, but I would read on how the answer was obtained if I were you.

The Lewis Dot Structure represents the number of electrons in a molecule or an ion. Hopefully, you will learn to be able to figure this out when I'm done explaining. You start with the Periodic Table, and you find what elements there are in your equation. Now, the way the table is set up, you should be able to easily find SOME of the electron count. Looking at the table you have groups and periods. We are dealing with the groups for electron count, so the table should have hydrogen at the top left in group 1, and helium in the far corner with group 18. This may be difficult to understand, you see, all molecules and ions want to be like the Noble gasses of group 18 (Neon, Argon, Krypton, etc.), to have 8 electrons (2 for helium) in their presence to balance out their protons and make them stable and nonreactive. With this in mind, you know that Group 18, the Noble gasses have all 8 electrons on them and are, in a way, perfect. Group 17 (Fluorine, Chlorine, Bromine, etc.) are one electron off of having the perfect 8 because it is directly to the left of group 18. This gives them a positive charge of 1 when in an ionic state. Group 16 (Oxygen, Sulfur, Selenium, etc.) has a positive 2 charge, as it is 2 to the left of group 18. Group 15 (Nitrogen, Phosphorus, Arsenic, etc.) is 3 to the left of group 18, so it has a charge of positive 3. Now, group 14 (carbon, Silicon, Germanium, etc.) is the equalizer, as it is in the center of the table when considering electrons, therefore, they have NO charge, but still wants to have the 8 electrons. Now we will flip to group 1 (Hydrogen, Lithium, Sodium, etc.). Group 1 has 1 EXTRA electron, so it gives it a negative charge, this causes it to want to give this electron away to another ion. Group 2 (Beryllium, Magnesium, Calcium, etc.) has 2 extra electrons, giving it a charge of negative 2. Group 13 (Boron, Aluminum, Gallium, etc.), not 3, has a charge of negative 3. Now, when combining to form molecules, sometimes there just aren't enough electrons for all of the elements to have a perfect 8 surrounding each element, so the elements then begin to share electrons, so that each electron is in a pair. If there are too many electrons, then all of the extra electrons are placed surrounding the central element, but this only occurs when you have an ion.

Now that that is explained, I can continue on the actual question. SO2 has 1 Sulfur atom, and 2 Oxygen atoms, all in group 16, so all have a positive charge of 2. You still with me? Good, now we know that we have the 6 electrons for each element in group 16, giving us a total of 18 electrons to work with. Now, we determine where each element goes. Sulfur is all alone, so it goes in the center with the two oxygen ions surrounding it, so it should look like this:

O S O

Now, because it is a molecule, we need to attach them to each other by sharing the electrons. The most electrons that can be shared between two ions are 6, called a triple bond, and is represented as three separate lines. A double bond shares 4 electrons and is represented as two separate lines (=). All elements in a molecule or a multiple element ion REQUIRE that you have at least 2 electrons shared and represented as a single line connecting the two (-).

O-S-O

Now that they are connected, we can begin distributing the electrons (in pairs!) to the different elements so they all have 8 electrons surrounding the element using the electrons we have.

:::O-S:-O:::

This however, is not correct, as Sulfur only has 6 electrons surrounding it, even though the two oxygen have 8, so we need to share more electrons. Lets try a double bond on both oxygen with the sulfur.

::O=S=O::

Success! Both oxygen have their 8 electrons from the double bond with sulfur and the four outer electrons (:), and the sulfur has its 8 from the two double bonds with oxygen. But did we use up all of the electrons exactly? Let's double check. We have 2 "=", so that's 8 electrons, then we have 4 ":", so that makes 8 electrons, so eight plus eight makes the sixteen electrons we had at the start. This means that this is the correct Lewis Dot Structure!