 SWBAT Categorize electrons by energy levels, sublevels, and orbitals using the atomic model  SWBAT create Bohr models and atomic diagrams using knowledge of electron energy levels

 Lecture and guided notes (15 min)  White board practice (15 min)  Bohr Model poster (20 min)  Practice questions (15 min)  Exam Alignment Guides (10 min)

What is the difference between the models in group a and group b Group AGroup B

 Niels Bohr: (1913) proposed that an electron is found only in specific circular paths, or orbits, around the nucleus  Each electron has a fixed energy level Energy level

1. Draw a small circle below the text that will represent the nucleus of the atom In the circle write: the elemental symbol the number of Protons and Neutrons Carbon Atomic # = 6 Mass # = 12 Atomic mass = amu C 6p + 6n 0

2. Draw a larger circle around the nucleus circle to represent the first energy level for electrons Add more circles outside to include all of the energy levels you need for the atom. This is the same as the period row Carbon is in Period two and therefore needs two energy levels Carbon Atomic # = 6 Mass # = 12 Atomic mass = amu C 6p + 6n 0

3. Add electrons, as small dots, to each energy level as allowed until you have the proper number of electrons. Carbon Atomic # = 6 Mass # = 12 Atomic mass = amu The number of electrons should be equal to the number of protons or atomic number Energy Level # of e C 6p + 6n 0

You now have a complete Bohr Diagram Carbon Atomic # = 6 Mass # = 12 Atomic mass = amu C 6p + 6n 0

 Draw the Bohr model for sodium (Na) ◦ How many protons and neutrons does sodium have? ◦ How many electrons does sodium have? ◦ How many energy levels does sodium have (hint: what row is it in?)

Richard Feynman

 Electrons move around the nucleus at certain energy levels, but it’s a little more complicated.  Within these levels, we have orbitals, or energy sublevels, which are regions where an electron is likely to be found.  For example, you are an 11 th grader (your energy level), but you are likely to be found in Chemistry, Algebra II, and Spanish III (your regions, your orbitals).

 Atomic orbital: describes the electron’s probable location  Principal quantum numbers: indicate the relative sizes and energy of atomic orbitals, there are 4 of these numbers ◦ ex: principal energy level, n  Energy sublevels: describes the shape of the orbital, can be s, p, d or f

 When it’s spinning fast, we can’t see the blades but we know they’re likely to be in a certain area.  That’s what the orbital tells us about the electron!

 Each orbital corresponds to a different shape  s orbitals ◦ spheres  p orbitals ◦ dumbbell-shaped 2 electrons 6 electrons

 d orbitals ◦ like balloons tied together or balloons with a hula hoop  f orbitals ◦ like balloons with cupcake wrappers or bracelets? 10 electrons 14 electrons

Principal Energy Level Number of Sublevels Type of Sublevel Maximum number of electrons n = 11 1s (1 orbital) 2 n = 2 2 2s (1 orbital), 2p (3 orbitals) 8 n = 33 3s (1 orbital), 3p (3 orbitals), 3d (5 orbitals) 18 n = 4 4 4s (1 orbital), 4p (3 orbitals), 4d (5 orbitals), 4f (7orbitals) 32

1. What is the energy level for carbon? 2. What sublevels are contained in the carbon atom? 3. What orbitals are related to each of these sublevels? 4. How many electrons are in each orbital and sublevel?

Principal Energy Level SublevelsCorresponding number of orbitals Number of electrons n = 11s1 orbital2 n = 2______ 2p 1 orbital ______________ ______ 2

Principal Energy Level SublevelsCorresponding number of orbitals Number of electrons n = 11s1 orbital2 n = 22s 2p 1 orbital 3 orbitals 2222

1. What is the principal energy number? 2. How many sublevels does P have? 3. How many orbitals does P have? 4. How many protons, neutrons and electrons does P have?

1. What is the principal energy number? 2. How many sublevels does Cr have? 3. How many orbitals does Cr have? 4. How many protons, neutrons and electrons does Cr have?

1. What is the principal energy number? 2. How many sublevels does Br have? 3. How many orbitals does Br have? 4. How many protons, neutrons and electrons does Br have?

 Kayla claims that the n=2 energy level has 4 electrons because it has 4 orbitals. Is she correct? Why or why not?

 Troy claims that the principal energy level always equals the number orbitals at that level, and so energy level n=3 has 3 orbitals. Is Troy correct? Why or why not?

 Pick a paper with an element on it.  Make a drawing of the Bohr model for that element  Answer the questions (from the small question sheet) on the back of your model

Complete the following practice problems  p.132 #7  p. 152 #32, 33, 34, 37, 38

1. Draw the orbitals for n = 1,2 and 3 and write how many electrons can be in that energy level 2. Draw the Bohr model for oxygen, sodium and silicon