Fall 2011 – Week 8 (Electrons) Chemistry catalysts Fall 2011 – Week 8 (Electrons)
Catalyst (5 min) 9/26/11 Electron Orbitals EQ: How are electrons organized in an atom? How were the models of JJ Thomson, Niels Bohr, and Erwin Schrodinger different from each other with respect to their ideas about electrons in an atom? Draw pictures if it will help you explain yourself. (Hint: Use your foldable.)
Catalyst JJ Thomson believed negative electrons floated within a positive sphere, & look similar to raisins in a plum pudding. Niels Bohr believed electrons orbited the positive nucleus in circles like planets orbiting the sun. Erwin Schrödinger believed electrons travelled extremely quickly around the positive nucleus in recognizable patterns.
s, p, d, & f Modern Orbital Theory There are four kinds of electron orbitals: s, p, d, & f Lower energy orbitals are closer to the nucleus and higher energy orbitals are farther from the nucleus. Each orbital can hold a maximum of 2 electrons
s Orbitals s orbitals are spherical, and there is 1 in each energy level Examples: 1s, 2s, 3s, 4s, 5s, 6s, 7s
p Orbitals p orbitals are shaped like dumbbells, and there are 3 in each energy level Examples: 2p, 3p, 4p, 5p, 6p, 7p
d Orbitals d orbitals are shaped like clovers, and there are 5 in each energy level Examples: 3d, 4d, 5d, 6d
f Orbitals f orbitals are oddly shaped, and there are 7 in each energy level Examples: 4f, 5f, 6f, 7f
Reviewing orbitals Each orbital can hold ____ electrons. 2 Each orbital can hold ____ electrons. There is ____ kind of s orbital. Therefore, s can hold ____ electrons. There are ___ kinds of p orbitals. Therefore, p can hold ___ electrons. There are ___ kinds of d orbitals. Therefore, d can hold ___ electrons. There are ___ kinds of f orbitals. Therefore, f can hold ___ electrons. 1 2 3 6 5 10 7 14
Orbitals Orbital names have 2 parts The energy level is the first part. For example: n=1, n=2, n=3, etc. The shape of the orbital is the second part. For example: s, p, d, or f Examples of orbital names include 1s, 2p, 3d, 3f, 4d, 5s, 5d, etc.
Do you notice any patterns on the periodic table that match the # of electrons in each orbital shape? s = 2, p = 6, d = 10, and f=14
Notes: Atomic Orbitals Summary of Principal Energy Levels, Sublevels and Orbitals: Principal Energy Level Type of Sublevel Maximum Number of Electrons n = 1 1s 2 n = 2 2s, 2p 8 (2+6) n = 3 3s, 3p, 3d 18 (2+6+10) n = 4 4s, 4p, 4d, 4f 32 (2+6+10+14)
Notes: Orbital Diagrams Electron Configuration Orbital Diagrams Fold your paper so that you have two columns – the left side column should be larger than the right
Notes: Orbital Diagrams The Aufbau Principle states that an electron will occupy the lowest energy level orbital available Hydrogen 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Notes: Orbital Diagrams The Pauli Exclusion Principle states that two electrons in the same orbital will have opposite spins Helium 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Notes: Orbital Diagrams Lithium 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Notes: Orbital Diagrams Beryllium 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Notes: Orbital Diagrams Boron 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Notes: Orbital Diagrams Hund’s Rule states that electrons in an equal energy level orbital will go in singly before doubling up Carbon 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Notes: Orbital Diagrams Hund’s Rule states that electrons in an equal energy level orbital will go in singly before doubling up Nitrogen 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Notes: Orbital Diagrams Hund’s Rule states that electrons in an equal energy level orbital will go in singly before doubling up Oxygen 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Practice Draw the orbital diagrams for fluorine, neon and sodium in your notes. 3s 2p 2p 2p 3s 2s 2p 2p 2p fluorine 3s 1s 2s neon 2p 2p 2p 1s 2s sodium 1s
Notes: Orbital Diagrams 3p 3p 3p 3s Energy Have students copy blank, then do oxygen together as a class. 2p 2p 2p 2s 1s
Draw orbital diagrams for: Homework Draw orbital diagrams for: Aluminum Phosphorous Chlorine
Catalyst (5 min) 9/28/11 Electron Configurations EQ: How do we represent the organization of electrons in an atom? Draw an electron orbital diagram for sulfur.
Catalyst Sulfur Energy 4s 3p 3p 3p 3s 2p 2p 2p 2s 1s Have students copy blank, then do oxygen together as a class. Energy 2p 2p 2p 2s 1s
Principles of Orbital Filling The Aufbau Principle states that an electron will occupy the lowest energy level orbital available The Pauli Exclusion Principle states that two electrons in the same orbital will have opposite spins Hund’s Rule states that electrons in an equal energy level orbital will go in singly before doubling up
Review: Orbital Diagrams Hydrogen 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Review : Orbital Diagrams Helium 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Review : Orbital Diagrams Lithium 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Review: Orbital Diagrams Beryllium 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Review: Orbital Diagrams Boron 3s Energy Use for hydrogen through boron (click for Aufbau before hydrogen, then click for Pauli before helium) 2p 2p 2p 2s 1s
Review: Orbital Diagrams Carbon 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Review: Orbital Diagrams Nitrogen 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Review: Orbital Diagrams Oxygen 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Review: Orbital Diagrams Fluorine 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Review: Orbital Diagrams Neon 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Review: Orbital Diagrams Sodium 3s Energy Use for carbon to oxygen 2p 2p 2p 2s 1s
Homework: Orbital Diagrams Aluminum Phosphorous 4s 4s 3p 3p 3p 3p 3p 3p 3s 3s Energy Have students copy blank, then do oxygen together as a class. Energy 2p 2p 2p 2p 2p 2p 2s 2s 1s 1s
Homework: Orbital Diagrams Chlorine 4s 3p 3p 3p 3s Have students copy blank, then do oxygen together as a class. Energy 2p 2p 2p 2s 1s
Electron Configuration Electron configuration is a less complicated way to show the electrons in an atom. Number of electrons in the orbital 2s 1s1 Energy becomes Use for carbon to oxygen 1s Orbital Diagram for Hydrogen The Orbital
Electron Configuration Energy 1s 2s He becomes 1s2 Energy 1s 2s Li becomes 1s2 2s1
Electron Configuration Energy 1s 2s Be becomes 1s2 2s2 Energy 1s 2s B 2p becomes 1s2 2s2 2p1
Practice Write the electron configuration for carbon through neon. Carbon = 1s22s22p2 Nitrogen = 1s22s22p3 Oxygen = 1s22s22p4 Fluorine = 1s22s22p5 Neon = 1s22s22p6
Electron Configuration Classwork/Homework On a separate sheet of paper, make 2 columns just like you did Monday. Keep going! I need to see orbital diagrams & electron configurations for elements #11-22 (sodium through titanium). Electron Configuration Orbital Diagrams
Classwork/Homework Energy 4p 4p 4p 3d 3d 3d 3d 3d 4s 3p 3p 3p 3s 2p 2p Have students copy blank, then do oxygen together as a class. 2p 2p 2p 2s 1s
Homework Write electron configurations for Al, P, Cl, & S (aluminum, phosphorous, chlorine, and sulfur). Hint: You should have the electron orbital diagrams for all of these from last night’s homework and today’s warm-up.
John Dalton JJ Thomson Ernest Rutherford Niels Bohr Atomic Models
Directions for Atomic Models Review For each section, describe: the structure of the atom with a picture the structure of the atom using words the new part of the atom discovered the experiment that led to its discovery Use complete sentences!
Catalyst (5 min) How many types of s, p, d, & f orbitals are there? 9/28/11 Electron Configurations EQ: How do we represent the organization of electrons in an atom? How many types of s, p, d, & f orbitals are there? How many electrons will fit in one orbital? If phosphorous has 15 electrons, where is each one located?
Catalyst Review 1 & 2: s = 1 type, 2 electrons p = 3 types, 6 electrons d = 5 types, 10 electrons f = 7 types, 14 electrons 3: Phosphorous has 15 electrons. 1s2 2s22p6 3s23p3 1st energy level has 2 electrons in the 1s orbital 2nd energy level has 8 electrons in the 2s & 2p orbitals 2 electrons in 2s, 6 electrons in 2p 3rd energy level has 5 electrons in the 3s & 3p orbitals 2 electrons in 3s, 3 electrons in 2p
Homework: Orbital Diagrams Aluminum: 1s22s22p63s23p1 Phosphorous 1s22s22p63s23p3 4s 4s 3p 3p 3p 3p 3p 3p 3s 3s Energy Have students copy blank, then do oxygen together as a class. Energy 2p 2p 2p 2p 2p 2p 2s 2s 1s 1s
Homework: Orbital Diagrams Chlorine 1s22s22p63s23p5 Sulfur 1s22s22p63s23p4 4s 4s 3p 3p 3p 3p 3p 3p 3s 3s Energy Have students copy blank, then do oxygen together as a class. Energy 2p 2p 2p 2p 2p 2p 2s 2s 1s 1s
Labeling s, p, d, & f s p d f
Writing Electron Configurations Carbon 1s2 2s2 2p2 s p d C f
Writing Electron Configurations Magnesium 1s2 2s2 2p6 3s2 s p d f Mg
Writing Electron Configurations Chlorine 1s2 2s2 2p6 3s2 3p5 s p d f Cl
Writing Electron Configurations Arsenic 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p3 s p d f As
1s22s22p3 Nitrogen 1s22s22p63s23p64s23d104p1 Gallium Identifying Elements 1s22s22p3 Nitrogen 1s22s22p63s23p64s23d104p1 Gallium
1s22s22p63s23p3 Phosphorous 1s22s22p63s23p64s23d104p65s1 Rubidium Identifying Elements 1s22s22p63s23p3 Phosphorous 1s22s22p63s23p64s23d104p65s1 Rubidium
Catalyst (5 min) 9/29/11 Valence Electrons EQ: What are valence electrons? Write the electron configuration for neon. Write the electron configuration for aluminum. Write the electron configuration for argon. Write the electron configuration for calcium.
Catalyst Review Neon 1s22s22p6 Aluminum 1s22s22p63s23p1 Argon 1s22s22p63s23p6 Calcium 1s22s22p63s23p64s2
What is a Valence Electron? Valence electrons are the electrons in the highest energy level Valence electrons are the outermost electrons
What is a Valence Electron?
What is a Valence Electron? 1 8 2 3 4 5 6 7
Practice Determine the number of valence electrons for the following elements: Lithium Carbon Oxygen Neon 1 4 6 8
Lewis Dot Structures There is one more way to illustrate the electrons in an atom. Lewis Dot Structures show just the valence electrons. The dot represents Hydrogen’s one valence electron H The symbol represents the Hydrogen nucleus
Lewis Dot Structures H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar
Writing Valence Electrons
Catalyst Review Neon 1s22s22p6 Aluminum 1s22s22p63s23p1 Argon 1s22s22p63s23p6 Calcium 1s22s22p63s23p64s2
Abbreviated Electron Configurations Write the electron configuration for neon, aluminum, argon and calcium. Neon 1s22s22p6 Aluminum 1s22s22p63s23p1 Argon 1s22s22p63s23p6 Calcium 1s22s22p63s23p64s2 Do you see any patterns that could help you write these in a shorter way? Write the electron configuration for neon, aluminum, argon and calcium. Neon 1s22s22p6 Aluminum 1s22s22p63s23p1 Argon 1s22s22p63s23p6 Calcium 1s22s22p63s23p64s2 Do you see any patterns that could help you write these in a shorter way? becomes [Ne]3s23p1 becomes [Ar]4s2
Abbreviated Electron Configurations Calcium: 1s22s22p63s23p64s2 Use a noble gas symbol to represent the first part of the electron configuration. Neon is closest to Argon, Ar: 1s22s22p63s23p6
Abbreviated Electron Configurations Calcium: 1s22s22p63s23p64s2 Use a noble gas symbol to represent the first part of the electron configuration. Calcium is closest to Argon, Ar: 1s22s22p63s23p6 Add the remaining electrons. [Ar] 4s2
Catalyst (5 min) 9/30/11 Electron EQ: What do I need to know for the midterm next Friday (10/7)? Write the FULL electron configuration for Germanium (Ge). Now abbreviate it.
Catalyst Germanium 1s22s22p63s23p64s23d104p2 [Ar] 4s23d104p2