The movement of electrons in atoms. Electron shells

The title of the Project: The movement of electrons in atoms. Electron shells

This virtual laboratory is intended for use in chemistry classes on the following topics:

  • 8th grade. Chapter I. “The movement of electrons in atoms.”
  • 8th grade. Chapter VIII. “Periodic system of chemical elements”

Purpose of the virtual laboratory work:

  • to visualize electron shells and their capacity.
  • to determine the relationship between electron shells and the element position in the periodic table

Virtual experiment: Electron shells

Characteristics of atomic particles

Table 1

ParticlesMass numberCharge numberNote
proton+1The number of protons is equal to the ordinal number of the element
neutron0The number of neutrons can be found by the following formula:N=А -Z , А -atomic mass number, Z – number of protons
electron-1The number of electrons is equal to the ordinal number of the element
  1. Start the simulation. You will be testing two different screens and play games in the end to check your ability to use what you have learned. Let’s take a look at the Atom screen first.

  1. The screen shows an empty model of the atom and the particles it consists of. By holding down the left mouse button, you can drag them into the atomic model.

  1. Place a single proton in the center of the atom. The element name will immediately appear on the screen. In the periodic table on the right,you can see the symbol of the formed element. The lower section shows the charge and mass number of the element. In addition, by checking the boxes in the “Show” section, you can show or hide the name of the element, whether it is a neutral atom or ion, stable or unstable.

  1. Add an electron to the atomic model. Place it in an outer orbital. What did you notice? The periodic number of an element in the periodic table corresponds to the number of its occupied energy levels. For example, the element hydrogen is in the first period of the periodic table. This means it has only one occupied energy level, which contains one electron.

  1. Build a helium atom! Based on the periodic table, helium has atomic number 2, meaning it has 2 protons and 2 electrons in the same energy level.

  1. Explore the arrangement of electrons in orbitals using lithium as an example!Lithium sits third in the periodic table, meaning it has 3 protons and 3 electrons. Place these particles in their designated spots. You’ll observe that the third electron occupies the second energy level. This is because the first energy level can only hold up to two electrons.

  1. Check the box in the “Stable/Unstable” section. You might notice the resulting atom is unstable. To make it stable, add neutrons.Look up the element’s atomic and mass number in the periodic table. The provided periodic table doesn’t show the mass number, therefore refer to a standard Mendeleev table. Use the formula  in Table 1 to determine the necessary number of neutrons.Add the calculated number of neutrons to your atom model. 

  1. Build a Neon atom. To do this, repeat steps 5-6. In the periodic table, neon’s atomic number is 10, and the period number is 2. This means that it contains 10 protons, 10 electrons and two energy levels. The mass number is 20, which means the number of neutrons is 10. Arrange the particles in their places. You may notice that there are eight electrons at the second energy level. The number of the group in which the element is located in the periodic table indicates the number of electrons at the outer shell. Check which group the neon atom is in. Draw conclusions.

  1. Now, to summarize the work, go to the “Game” section and test your knowledge. There are 4 different games in this section. Each game consists of 5 stages. A clock image is displayed in the lower left corner of the screen. By turning it on, you can compete with your partner for speed.

  1. The first game is called “Find the element!”. You must identify the symbol of the element hiding in the periodic table according to a given atomic model.

  1. In the second game, you will determine the mass number and charge of the atom.

  1. In the third, you must add the missing information to the element symbol.

  1. In the fourth game, you need to identify an element by creating its symbol.

Conclusion:

In this virtual lab, students explored the atomic structure by studying protons, neutrons, and electrons. They delved deeper through experiments on the arrangements of electrons in electron shells. As a result, they discovered a connection between electron shell structure and the element’s position on the periodic table.