Key concepts

The electrons surrounding an atom are situated in regions approximately the nucleus referred to as “energy levels”. An energy level represents the 3-dimensional space surrounding the nucleus where electrons room most most likely to be. The first energy level is closest come the nucleus. The second energy level is a small farther away than the first. The 3rd is a tiny farther away 보다 the second, and so on.Each energy level have the right to accommodate or “hold” a different variety of electrons before added electrons start to go into the next level. Once the first energy level has actually 2 electrons, the next electrons get in the 2nd energy level until the 2nd level has 8 electrons. When the 2nd energy level has 8 electrons, the following electrons get in the third energy level till the 3rd level has actually 8 electrons.When the third energy level has actually 8 electrons, the next 2 electrons get in the fourth power level.The electrons in the energy level the furthest from the nucleus are called valence electrons.Atoms in the same column (group) in the periodic table have the same variety of valence electrons.


Students will again focus on the very first 20 elements. Students will very first look at a diagram and also animation to recognize the straightforward pattern the the plan of electron on power levels around an atom. Students will certainly be provided cards v information about the electrons and also energy levels for each that the first 20 atoms. They will again shot to correctly complement the cards with each element.

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Students will have the ability to interpret the information offered in the routine table to describe the setup of electrons on the energy levels about an atom.


Download the student activity sheet, and distribute one every student once specified in the activity. The task sheet will certainly serve together the “Evaluate” ingredient of every 5-E lesson plan.

About this Lesson

Be certain that the 20 atom surname cards room posted approximately the room. Friend will need the five cards top top the best hand next of every sheet. This lesson is intended as a follow-up to thing 4, lesson 2.

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

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

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Show students that you have 80 cards (4 because that each that the very first 20 elements). Prior to distributing the cards, explain that each card includes information about electrons and energy levels for the an initial 20 aspects of the periodic table. The students’ task is to review the map carefully, number out which aspect the card is describing, and put the card at the clues in the room for the element. Remind students the they will have to count the electron in stimulate to determine each atom. Once students understand what their assignment is, distribute the cards to groups.


Have students look for trends in rows and also columns that the first 20 elements in the periodic table.

Continue to task the image Periodic table of power levels for aspects 1–20 and have college student look at their activity sheets to find patterns in the number of electrons within each energy level.

Have college student look in ~ the periods (rows walk across).

Number of energy levels in every period

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

How the electrons to fill in the power levels

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