Radioisotopos

Atomic Musical Chairs
Lesson Plan and Answer Key Objectives: Students will be able to… 1. Identify the different parts of an atom. 2. Determine the atomic number, atomic mass, & the # of protons, neutrons and electrons for each atom. 3. Realize that electrons are not static, but always moving. 4. Know the relationship between the number of electrons to the type of atom. 5. Differentiate betweenions and isotopes. 6. Recognize that atoms have a numeric relationship in the periodic table. 7. Understand the connection between energy levels and valence electrons to the shape of periodic table. Materials: • • • • • 40 balls of two colors (18 one color = protons, 22 another color = neutrons, ex. Tennis balls, rubber balls, wiffle balls, golf balls, Nerf balls, etc…) 2 Small Round LaundryBaskets (1 for the nucleus, 1 to store unused balls) 10 – 18 Chairs Periodic Tables Music

Opener (ask class): • • • • What do we know about the periodic table? How is one atom different from another? What do we know about the number of electrons? What do we know about electron orbitals?

Explain: 1. Display periodic tables in easy to see locations or have half your students as electrons and theother half holding periodic tables, then switch roles. 2. Arrange chairs in concentric circles with rings of 2, 8, & 8. The laundry basket is the “nucleus” at the center. 3. Parts of the Atom: a. The nucleus holds the protons and neutrons. The number of protons = the atomic number. Ex. Hydrogen has an atomic number of 1, place one tennis ball in the nucleus. Protons have a positive (+) charge. b.The number of neutrons = {the atomic mass of the atom – the atomic number}. Hydrogen has an atomic mass of 1 (round
Original Lesson Donated to www.middleschoolscience.com by Marc Bonem of the Science and Arts Academy, Des Plaines, IL and edited/revised by Liz LaRosa. Reproduction for commercial use or profit is not permitted © 2005.

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the atomic mass to the nearest whole number) and anatomic number of 1. Therefore 1 – 1 = 0. There are no neutrons in Hydrogen. Sometimes the # of neutrons and the # of protons are the same, sometimes they are not. Neutrons have no charge and are considered neutral. c. Each circle is an energy level for electrons. The number of electrons = the atomic number. The atomic number of Hydrogen is 1, therefore it has 1 electron. Electrons have a negative ( - )charge. d. Notice there are two chairs in the first level, eight in the next? Each energy level has a certain amount of space for the electrons to move in. e. We will add one color ball for the protons, the other color for the neutrons for each atom. We will fill in each atom one electron at a time. Each student will be an electron. Start Activity: 1. Have students line up or stand in a circlearound the outside of the atom. Have half the students hold a periodic table or have periodic tables that are easy to see and access. 2. The first element is Hydrogen, have the students tell you how many balls to throw into the nucleus. (ex. 1 tennis ball for proton, no rubber balls for neutrons) 3. Ask the students, “How many electrons should enter the atom?” (just 1) 4. The first student on lineshould enter the atom and take a seat in the first energy level. 5. At this point, you can turn on the music; the electron should walk around until you turn off the music, then take a seat. Why? (Electrons are always moving, when the music stops, it is just where they are at that moment in time, it’s not a permanent position.) You can turn the music on and off again a couple of times for fun andhave the elelctron seated when the music stops. 6. Have the student that was the electron step out of the atom and to the end of the line. 7. Now try Helium. Ask, “How many protons?” (2) “What is the Atomic Mass?” (4) “How many Neutrons?” (4-2=2) “How many Electrons?” (2) 8. Throw in new balls until you have 2 proton balls and 2 neutron balls. Have the next 2 students enter as electrons. 9. At...