Key concepts

The electrons surrounding an atom are situated in regions about the nucleus called “energy levels”. An energy level represents the 3-dimensional room surrounding the nucleus where electrons space most likely to be. The very first energy level is closest to the nucleus. The second energy level is a little farther away 보다 the first. The 3rd is a little farther away 보다 the second, and also so on.Each energy level have the right to accommodate or “hold” a different variety of electrons before added electrons begin to enter the next level. Once the very first energy level has actually 2 electrons, the next electrons go into the 2nd energy level till the 2nd level has actually 8 electrons. When the 2nd energy level has 8 electrons, the following electrons get in the third energy level until the third level has 8 electrons.When the 3rd energy level has actually 8 electrons, the next 2 electrons get in the fourth power level.The electrons in the energy level farthest from the cell core are dubbed valence electrons.Atoms in the same obelisk (group) in the periodic table have the same number of valence electrons.


Students will certainly again focus on the an initial 20 elements. Students will first look at a diagram and animation to understand the simple pattern of the arrangement of electrons on power levels approximately an atom. Students will certainly be offered cards through information around the electrons and energy levels for each of the first 20 atoms. They will certainly again shot to correctly complement the cards through each element.

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Students will have the ability to interpret the information provided in the regular table to describe the setup of electrons on the power levels approximately an atom.


Download the student task sheet, and distribute one every student when specified in the activity. The task sheet will serve together the “Evaluate” component of each 5-E great plan.

About this Lesson

Be certain that the 20 atom name cards are posted approximately the room. Girlfriend will need the five cards top top the best hand next of each sheet. This great is intended together a follow-up to chapter 4, great 2.

For great 4.3, students deserve to play the periodic Table Game, game #2. This is one online variation of the routine table card game from this lesson the you deserve to assign as class work or homework ~ students have actually played the game in the classroom.

Have groups work with each other to location each card v its exactly atom.

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Show students the you have 80 cards (4 because that each of the first 20 elements). Prior to distributing the cards, describe that each card consists of information about electrons and energy levels for the an initial 20 facets of the regular table. The students’ job is to check out the map carefully, figure out which facet the card is describing, and also put the card at the spot in the room for the element. Remind students the they will have to count the electron in bespeak to determine each atom. As soon as students understand what their assignment is, distribute the cards come groups.


Have students watch for patterns in rows and also columns of the very first 20 aspects in the regular table.

Continue to job the picture Periodic table of energy levels for facets 1–20 and also have college student look at their activity sheets to uncover patterns in the variety of electrons in ~ each energy level.

Have college student look at the durations (rows walk across).

Number of power levels in each period

The atom in the first period have electrons in 1 energy level.The atoms in the second period have electron in 2 power levels.The atoms in the third period have electron in 3 energy levels.The atom in the fourth period have electron in 4 energy levels.

How the electrons to fill in the energy levels

First energy level = 1, 2Second power level = 1, 2, 3, …8Third energy level = 1, 2, 3, …8