Central Atoms in lewis Structures

[Reece Fong 2k]

How do we know what the central atom will be? What are the rules and are there exceptions? (I know Carbons usually form the central atom and hydrogens are not central atoms)

[Riya 14B-2]

Hey!

I believe the central atom is the element with the lowest ionization energy/lowest electronegativity. Additionally, the element with the lowest subscript in the compound is often the central atom.

Hope this helps :)

[SuryaDham 3E]

The lowest ionization energy usually corresponds to the central atom.

[Lauren Brotman 2F]

Yes, the atom with the lowest ionization energy is usually the central atom. You are also correct about hydrogen because hydrogen doesn't form more than one bond, so it's never the central atom.

[Cindy Vo 3E]

The atom with the lowest ionization energy is typically the central atom. Hydrogen is never the central atom because it can only form one single bond.

[HannahArabi14a]

When drawing Lewis structures, you have to put into consideration what the electronegativity trend is the elements that are present, either by itself or in a chemical compound. Count the electrons that are in each elements and consider the subscript of how many of one element are present. For example, if it's C2H2, we consider the electronegativity. In this case we would find that carbon has the increasing electronegativity compared to hydrogen, therefore carbon would be kept on the inside while hydrogen toward the outside. We have to keep in mind how many electrons we have: carbon we have 6 snd hydrogen we have 1, so in total if its C2H4 it's 14 valence electrons. For another examples of drawing lewis structures if we look at the chemical compound NO3, even though oxygen is more electronegative compared to nitrogen there are more oxygen atoms present so it would surround the nitrogen, instead of being the central atom.

Hope this helps.

[Kimberly_martinez2I]

The atom with the lowest ionization energy would be the central atom.

[Charlie Sjogren-Black]

The lowest ionization energy corresponds to the center atom.

[Naomi Christian 1E]

The central atom is the atom with the lowest ionization energy!

[Sammy Liu]

The central atom is usually the element with the smaller ionization energy.

Hope this helps!

[Emily2J]

The atom with the lowest ionization energy is typically the central atom.

[Martha Avila 1I]

Hello! So you are correct it is a rule that Hydrogen atoms cannot be in the center of your Lewis Structure. In order to determine what your central atom is you have to find the atom with the lowest ionization energy. You do this by following the following trend, ionization energy increases across a period and decreases down a group. Usually if you have a C atom it will typically be your central atom but not always. Hope this helps.

[605778346]

Hi, the central atom should be the atom with the lowest ionization energy. Ionization energy increase across a table and decreases down a group.

[Sarah3C]

Are there exceptions to the central atom rule? I know nitrogen and carbon are typically center, but I am not sure it always follows the electronegativity rule. Anybody know if this just a general rule/any specific cases?

[Mahima Manoj 1F]

The lowest ionization energy atom is usually the central atom