How to Write an Electron Configuration for an Atom of any Element

By eHow Hobbies, Games & Toys Editor

Chemistry is a subject students begin to study in high school. They can conceptualize the abstract nature of the atom. The atom has a core made of positive and neutral charged particles at the center and electrons in a cloud around it. The electrons inhabit orbitals that only allow two electrons at any one time. Write the electron configuration of an atom by noting which orbitals they occupy.

Define for which atom you want to generate the electron configuration. The element that you choose has an atomic number. The atomic number defines how many protons are in the nucleus of the atom and how many electrons are orbiting the nucleus.

Decide how many orbitals you need to put electrons in for the element of interest. The orbitals of the atom are composed of s, p, d and f type orbitals. As you progress through the periodic table, numerically, you put electrons into these orbitals. The 1s orbital is the first one filled. It can hold 2 electrons. Therefore, hydrogen and helium only use the 1s orbital.

Note which family of elements the atom of interest is a part of. Any element that inhabits a position in the first two columns fill the s orbitals. The last six columns of the periodic table fill the p orbitals. The ten columns in the middle of the table fill the d orbitals and the two rows of fourteen elements below the table are filling the f orbitals. The orbitals fill in the order of 1s and 2s, followed by 2p, 3p, 4p and 5p orbitals. This trend continues with the 3d, 4d, and 5d orbitals with 4f and 5f orbitals being the last to fill if they are present.

Determine which orbitals are required and what order electrons will fill them. The general rule of thumb is 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4f, 4d and 5p. The elements position on the table governs the order the electrons fill the orbitals. There are 3 p orbitals that hold 6 electrons, 5 d orbitals that hold 10 electrons and 7 f orbitals that hold 14 electrons.

Line up the orbitals that you need to fill and begin populating them based on the information given. Once you have filled the number of electrons that you have, you will have the electron configuration for the element.