The model of an atom we typically see is similar to the model below. This is a simplified model.
Electrons are found around the nucleus of an atom in what are called energy levels (shells), but these levels can be broken into 3 different sublevels (subshells) which are s, p, d and f. These sublevels are then broken up into different orbitals. Check out the image below. Could you imagine having to draw each of those images multiple times to develop a model of an atom? That would be very time consuming and difficult, so we use a different model. Although we typically use the Bohr's model, we can't forget about the different sublevels.
Attribution: haade, CC BY-SA 3.0 <http://creativecommons.org/licenses/by-sa/3.0/>, via Wikimedia Commons
The periodic table can be split up into four different sections which represent the sublevels. Check out the periodic table below.
Although we may not draw out a full model of the atom, the sublevels and orbitals can be used to help with identifying the elements we are working with and the number of valence electrons an element has. Overall, there are other models we can use. Two ways that they can be use is through creating Aufbau Diagrams and Electron Configurations. Watch the following video to learn about these two types of models.
https://youtu.be/hnwqcupzgqE
Check out the following simulation:
- Go to the following website: https://www.labxchange.org/library/items/lb:LabXchange:b257994a:lx_simulation:1
- Click "Start Simulation."
- Follow the instructions on the webpage.
Let's practice!
- Go to the following website: elearning.cpp.edu/learning-objects/atomic-electron-configurations/
- Read over the instructions then click "Energy Ladder" in the top right hand corner.
- Create an Aufbau diagram for the Noble gases.
- After you check your answer, look over the electron configuration and the location of the element on the periodic table.
- Go to the following website: www.khanacademy.org/science/chemistry/electronic-structure-of-atoms/electron-configurations-jay-sal/e/electron-configurations-exercise
- Complete the practice questions.