Atomic structure


  • To learn to describe the main particles of an atom and their arrangement in an atom.
  • Understand the structure of an atom.
  • Assemble atoms using different combinations of protons, neutrons, and electrons.

This virtual lab is designed for use in science lessons on the following topic:

  • Grade 6. Chapter I. “What is the structure of an atom?”

Virtual experiment

Modeling atom formation allows students the flexibility to explore how changing the number of protons, neutrons, and electrons affects the element, charge, and mass of a constructed atom.

The figure below shows the functions each button performs.

Particle characteristic (charge)

Under normal conditions, an atom is electrically neutral, that is, it has no charge: it has as many electrons as protons in its nucleus.

The nucleus of an atom is positively charged.

ParticlesMass numberCharge numberNote
proton+1The number of protons is equal to the ordinal number of the element
neutron0The number of neutrons is determined by a formula. You will learn this formula in chemistry class.
electron-1The number of electrons is equal to the ordinal number of the element


Step 1. Start the simulation: you will be presented with 3 different modes, “Atom”, “Symbol” and “Game”. In this work you will use the “Atom” mode.

Step 2. The screen presents the empty framework of the atomic model and its atomic particles (proton, neutron, electron). The structure of the atom is called the planetary model. At the center of the atom is the atomic nucleus and electrons revolve around the nucleus. The electrons are constantly in motion in specific orbits. The atomic nucleus is made up of protons and neutrons. These particles are stationary in the nucleus.

Step 3. You can move the particles into the atomic model by holding down the left mouse button. Place a proton in the center of the atom. The name of the element will immediately appear on the screen. On the right side, you can see the symbol of the element formed in the periodic table.

Step 4. The bottom section shows the charge and mass number of the element. The charge of the element depends on protons and electrons, while the mass number depends on protons and neutrons.

Step 5. You can specify or hide the name of the element by checking the “Show” section. Two other buttons that you don’t need now will be studied in high school. These buttons indicate whether the neutral atom or ion is stable or unstable.

Step 6. A hydrogen atom is made up of 1 proton and 1 electron. Therefore, place the electron in an orbital. The charge of the element will change to “0”. The hydrogen atom is ready.

Step 7. You can represent the electrons either in orbitals or as an electron cloud.

Step 8. The next element in the table is helium. It is made up of 2 protons, 2 neutrons, and 2 electrons. Add one proton to the nucleus of the atom. The number of protons determines the position of the element in the periodic table, so as you add protons, you move around the table.

Step 9. Place two neutrons next to the proton in the nucleus of the atom.

Step 10. Place two electrons in orbit. The helium atom is ready. The charge of the element is “0” and the mass number is “4”.

Step 11. The next element is lithium. It consists of 3 protons, 4 neutrons, and 3 electrons. Create the element.

Step 12. The position of an element in Mendeleev’s periodic table is determined by the number of protons. The number of electrons in a neutral atom is equal to the number of protons. The mass number depends on the protons and neutrons. Although you can now correctly determine the number of protons and electrons, you will need a formula learned in high school to calculate the number of neutrons.

Thus, you can find the number of particles in other elements by looking them up on the internet. Below is the number of particles in the 10 elements after lithium.



Through virtual modeling, students were introduced to the structure of the atom. It was shown that chemical substances are in a certain sequence in Mendeleev’s periodic table according to the properties of each element.