Atomic structures
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The document is an introduction to atomic structure and electron configurations from the Rapid Learning Center's AP Chemistry series. It begins by defining atoms and their subatomic particles. It then explains how electrons are arranged in energy levels, subshells, and orbitals. The three main rules for determining electron configurations are also introduced: Aufbau principle, Hund's rule, and Pauli exclusion principle. Examples are provided of writing electron configurations using boxes and arrows notation as well as spectroscopic notation. Relationships between electron configurations and the periodic table are also discussed. Finally, the document briefly covers how ions form full valence shells in their electron configurations.
![AP Chemistry Rapid Learning Series - 12
Definition: Noble Gas Notation
Noble Gas – Group 8 of the Periodic
Table. They contain full valence shells.
Noble Gas Notation – Noble gas is
used to represent the core (inner)
electrons and only the valence shell
is shown.
Br
Spectroscopic
2
2
6
2
1s 2s 2p 3s 3p 6 4s 2 3d 10 4p 5
[Ar] 4s 2 3d 10 4p 5
Noble gas
The “[Ar]” represents the core electrons and only the valence electrons are shown.
39/60
Which Noble Gas Do You Choose?
How do you know which noble gas to use to
symbolize the core electrons?
Think: Price is Right.
How d you win on the Price is Right?
H
do
i
th P i i Ri ht?
By getting as close as possible without going over.
Choose the noble gas that’s closest without going over!
Noble Gas
He
2
Ne
10
Ar
18
Kr
40/56
# of electrons
36
Xe
54
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![AP Chemistry Rapid Learning Series - 12
Where Does the Noble Gas Leave Off?
How do you know where to start off after using a
noble gas?
Use the periodic table!
1s
He
2p
2s
Ne
3p
Ar
4s
3d
4p
Kr
5s
4d
5p
Xe
6p
Rn
3s
6s
4f
5d
7s
5f
6d
The noble gas fills the subshell that it’s at the end of.
Begin filling with the “s” subshell in the next row to show
valence electrons.
41/60
Noble Gas Notation Example
1
Determine the number of electrons to place.
2
Determine which noble gas to use.
3
Start where the noble gas left off and write spectroscopic
notation for the valence electrons.
Example:
As
Give the noble gas notation for As.
No charge written
Charge is 0
Atomic number for As = 33 = # of protons
0 = 33 - electrons
Electrons = 33
Place 33 electrons
Closest noble gas: Ar (18)
[Ar] 4s 2 3d 10 4p 3
Ar is full up through 3p
18 + 2 + 10 + 3 = 33
42/60
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Atomic structures
- 1. AP Chemistry Rapid Learning Series - 12 Rapid Learning Center Chemistry :: Biology :: Physics :: Math Rapid Learning Center Presents … p g Teach Yourself AP Chemistry Visually in 24 Hours 1/60 http://www.RapidLearningCenter.com Atomic Structure and Electron Configuration AP Ch i t R id Learning Series Chemistry Rapid L i S i Wayne Huang, PhD Kelly Deters, PhD Russell Dahl, PhD Elizabeth James, PhD Debbie Bilyen, M.A. © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com Rapid Learning Center www.RapidLearningCenter.com/ © Rapid Learning Inc. All rights reserved. 1
- 2. AP Chemistry Rapid Learning Series - 12 Learning Objectives By studying this tutorial you will learn… Basic structure of atoms How to determine the number of electrons How to place electrons in energy levels, subshells and orbitals How to show electron configurations using three methods How to write and understand Quantum Numbers 3/60 Concept Map Previous content Chemistry New content Studies Quantum Numbers Matter Location described by Made of Electrons Chemical properties determined by Atoms 3 ways to show configurations Boxes and Arrows Spectroscopic Notation Noble Gas Notation 4/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 2
- 3. AP Chemistry Rapid Learning Series - 12 Atomic Structure 5/60 Definition: Atom Atom - Smallest piece of matter that has the chemical properties of the element. Often called the “Building Block of Matter” 6/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 3
- 4. AP Chemistry Rapid Learning Series - 12 What’s in an Atom? An atom is made of three sub-atomic particles. Particle Location Mass Charge Proton Nucleus 1 amu = 1.67×10-27 kg +1 Neutron Nucleus 1 amu = 1.67×10-27 kg 0 Electron Outside the nucleus 0.00055 amu 9.10×10-31 kg -1 1 amu (“atomic mass unit”) = 1.66 × 10-27 kg 7/60 The Atom Electron cloud Nucleus Mass = M # of protons + # of neutrons Charge = # of protons Charge = - (# of electrons) Very small relative mass Overall Charge = # of protons - (# of electrons) Overall Mass = # of protons + # of neutrons 8/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 4
- 5. AP Chemistry Rapid Learning Series - 12 Protons Versus Electrons Protons Electrons + Charge - Charge Contributes to mass of atom Does not contribute significantly to mass of atom Found in nucleus Found outside nucleus # determines the “identity” of the atom # and configuration determine how the atom will react Cannot be lost or gained without changing which element it is (nuclear reaction) Can be lost or gained— results in an atom with a charge (ion) The ratio of protons to electrons determines the charge on the atom. 9/60 Electron Locations 10/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 5
- 6. AP Chemistry Rapid Learning Series - 12 Definition: Electron Cloud Electron cloud – It is the area outside of the nucleus where the electrons reside. 11/60 Electron Clouds Electron cloud Principle energy levels The electron cloud is made of energy levels. Subshells Energy levels are composed of subshells. Orbitals Subshells have orbitals. 12/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 6
- 7. AP Chemistry Rapid Learning Series - 12 Definition: Subshell and Orbital Subshell – A set of orbitals with equal energy. Orbital – Area of probability of the electron being located. Each orbital can hold 2 electrons. 13/60 Types of Subshells There are 4 types of subshells that electrons reside in under ordinary circumstances. Begins in energy level Number of equal energy orbitals Total number of electrons possible s 1 1 2 p 2 3 6 d 3 5 10 f Energ increases gy Subshell 4 7 14 14/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 7
- 8. AP Chemistry Rapid Learning Series - 12 Pictures of Orbitals s orbital 3 p orbitals 5 d orbitals 15/60 Electron Configuration 16/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 8
- 9. AP Chemistry Rapid Learning Series - 12 Definition: Electron Configurations Electron Configurations – g p g Shows the grouping and position of electrons in an atom. Since the number of electrons and their configuration determines the chemical properties of the atom it is important to understand them. atom, them Electron configurations use boxes for orbitals and arrow for electrons. 17/60 Aufbau Principle The first of 3 rules that govern electron configurations: 1 Aufbau Principle: Electrons must fill ( ) subshells (and orbitals) so that the total energy of atom is at a minimum. What does this mean? Electrons must fill the lowest available subshells El t t th l t il bl b h ll and orbitals before moving on to the next higher energy subshell/orbital. 18/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 9
- 10. AP Chemistry Rapid Learning Series - 12 Energy and Subshells The energy diagram below shows the relative energy levels. 6p 6s 5p 5d 4f 4d 5s 4p 3d 4s 3p 3s 2p Energy 2s 19/60 Subshells are filled from the lowest energy level to increasing energy levels. Not that this does not always go in numerical order. 1s Hund’s Rule The second of 3 rules that govern electron configurations. 2 Hund s Hund’s Rule: Place electrons in unoccupied orbitals of the same energy level before doubling up. How does this work? If you need to add 3 electrons to a p subshell, add 1 to each before beginning to double up. 20/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 10
- 11. AP Chemistry Rapid Learning Series - 12 Pauli Exclusion Principle The last of 3 rules that govern electron configurations. 3 Pauli Exclusion Principle: Two electrons that occupy th same orbital must have different spins. the bit l th diff t i “Spin” describes the angular momentum of the electron “Spin” is designated with an up or down arrow. How does this work? If you need to add 4 electrons to a p subshell, you’ll need to double up. When you double up, make them opposite spins. 21/60 Determining the Number of Electrons In order to properly construct an electron configuration, you must be able to determine how many electrons to use. Charge = # of protons – # of electrons Atomic number = # of protons Example: Br1- How many electrons does the following have? Charge = -1 Atomic number for Br = 35 = # of protons -1 = 35 - electrons Electrons = 36 22/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 11
- 12. AP Chemistry Rapid Learning Series - 12 Another Example In order to properly construct an electron configuration, you must be able to determine how many electrons to use. Charge = # of protons – # of electrons Atomic number = # of protons Example: Cl How many electrons does the following have? No charge written Charge is 0 Atomic number for Cl = 17 = # of protons 0 = 17 - electrons Electrons = 17 23/60 Applying the Rules Use the 3 rules of electron configurations. 1 Aufbau Principle: Electrons must fill subshells (and orbitals) so that the total energy of atom is at a minimum. 2 Hund’s R l Place electrons in unoccupied orbitals of the H d’ Rule: Pl l t i i d bit l f th same energy level before doubling up. 3 Pauli Exclusion Principle: Two electrons that occupy the same orbital must have different spins. Example: Cl Give the electron configuration for a Cl atom. No charge written Charge is 0 Atomic number for Cl = 17 = # of protons 0 = 17 - electrons Place 17 electrons 1s 2s Electrons = 17 40 9 8 17 16 15 14 13 12 11 7 6 5 1 3 2 2p 3s 3p 24/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 12
- 13. AP Chemistry Rapid Learning Series - 12 Spectroscopic Notation 25/60 Definition: Spectroscopic Notation Spectroscopic Notation – Shorthand way of showing electron configurations. The number of electrons in a subshell are shown as a superscript after the subshell designation. 1s 2s 2p 3s 3p 1s2 2s2 2p6 3s2 3p5 26/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 13
- 14. AP Chemistry Rapid Learning Series - 12 Writing Spectroscopic Notation 1 Determine the number of electrons to place. 2 Follow Aufbau’s Principle for filling order. 3 Fill in subshells until they reach their max (s = 2, p = 6, d = 10, f = 14). 4 The total of all the superscripts is equal to the number of electrons. Example: S Give the spectroscopic notation for S. No charge written Charge is 0 Atomic number for S = 16 = # of protons Electrons = 16 0 = 16 - electrons Place 16 electrons 2 + 2 + 6 + 2 + 4 = 16 1s 2 2s 2 2p 6 3s 2 3p 4 27/60 Electron Configurations and the Periodic Table 28/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 14
- 15. AP Chemistry Rapid Learning Series - 12 Configurations Within a Group Look at the electron configurations for the Halogens (Group 7). 1s 2s 2p 1 22 22 5 F Cl 1s2 2s2 2p6 3s2 3p5 Br 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p5 I All of the elements in Group 7 end with 5 electrons in a p subshell. 29/60 Configurations and the Periodic Table In fact, every Group ends with the same number of electrons in the highest energy subshell. Each area of the periodic table is referred to by the highest hi h t energy subshell that contains electrons. b h ll th t t i l t p-block s-block d-block s1 s2 p1 p2 p3 p4 p5 p6 d1 d2 d3 d4 d5 d6 d7 d8 d9 d10 f-block f1 f2 f3 f4 f5 f6 f7 f8 f9 f10 f11 f12 f13 f14 30/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 15
- 16. AP Chemistry Rapid Learning Series - 12 Periodic Table as a Road-Map Wondering how to remember the order of filling of the subshells? Just use the periodic table. 31/60 In order to do this, the “f” block needs to be placed in atomic order. (It’s usually written below to fit it on the paper) Periodic Table as a Road-Map To see the filling order of subshells, read from left to right, top to bottom! This tool shows that the 3d energy level is filled after the 4s energy level! 1s 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6p 6s 4f 5d 7s 5f 6d s subshells begin in level 1, so begin the s-block with “1s” p subshells begin in level 2, so begin the p-block with “2p” d subshells begin in level 3, so begin the d-block with “3d” f subshells begin in level 4, so begin the f-block with “4f” 32/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 16
- 17. AP Chemistry Rapid Learning Series - 12 Another Tool for Filling Order There is another tool commonly used to remember orbital filling order. 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 6s 6p 6d 7s To read the charge, move down one diagonal as far as possible, then jump to the top of the next diagonal and keep going. 7p 8s 33/60 Electron Configurations of Ions 34/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 17
- 18. AP Chemistry Rapid Learning Series - 12 Definition: Ion Ion – an atom that has g gained or lost electrons resulting in a net charge. Atoms gain and lose electrons to be in a more stable state. Usually, the “more stable state” is a full valence shell. Outermost shell of electrons 35/60 Full Valence Shell Ions Look at the electron configurations for the following: Br-1 p = 35 -1 = 35 - e e = 36 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 O2- p=8 -2 = 8 - e e = 10 +1 = 11 - e e = 10 +2 = 20 - e e = 18 1s 2 2s 2 2p 6 Na+ p = 11 1s 2 2s 2 2p 6 Ca2+ p = 20 1s 2 2s 2 2p 6 3s 2 3p 6 36/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 18
- 19. AP Chemistry Rapid Learning Series - 12 Full Valence Shell Ions What do you notice about each of these configurations? They all end with full p subshells. Br-1 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 O21s 2 2s 2 2p 6 Na+ 1s 2 2s 2 2p 6 Notice that O2- and Na+ have the same number and configuration of electrons. This makes them isoelectric. Ca2+ 1s 2 2s 2 2p 6 3s 2 3p 6 37/60 Noble Gas Configuration 38/56 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 19
- 20. AP Chemistry Rapid Learning Series - 12 Definition: Noble Gas Notation Noble Gas – Group 8 of the Periodic Table. They contain full valence shells. Noble Gas Notation – Noble gas is used to represent the core (inner) electrons and only the valence shell is shown. Br Spectroscopic 2 2 6 2 1s 2s 2p 3s 3p 6 4s 2 3d 10 4p 5 [Ar] 4s 2 3d 10 4p 5 Noble gas The “[Ar]” represents the core electrons and only the valence electrons are shown. 39/60 Which Noble Gas Do You Choose? How do you know which noble gas to use to symbolize the core electrons? Think: Price is Right. How d you win on the Price is Right? H do i th P i i Ri ht? By getting as close as possible without going over. Choose the noble gas that’s closest without going over! Noble Gas He 2 Ne 10 Ar 18 Kr 40/56 # of electrons 36 Xe 54 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 20
- 21. AP Chemistry Rapid Learning Series - 12 Where Does the Noble Gas Leave Off? How do you know where to start off after using a noble gas? Use the periodic table! 1s He 2p 2s Ne 3p Ar 4s 3d 4p Kr 5s 4d 5p Xe 6p Rn 3s 6s 4f 5d 7s 5f 6d The noble gas fills the subshell that it’s at the end of. Begin filling with the “s” subshell in the next row to show valence electrons. 41/60 Noble Gas Notation Example 1 Determine the number of electrons to place. 2 Determine which noble gas to use. 3 Start where the noble gas left off and write spectroscopic notation for the valence electrons. Example: As Give the noble gas notation for As. No charge written Charge is 0 Atomic number for As = 33 = # of protons 0 = 33 - electrons Electrons = 33 Place 33 electrons Closest noble gas: Ar (18) [Ar] 4s 2 3d 10 4p 3 Ar is full up through 3p 18 + 2 + 10 + 3 = 33 42/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 21
- 22. AP Chemistry Rapid Learning Series - 12 Comparing the Different Notations 43/60 Pros and Cons of Each Notation Each notation has it’s advantages and disadvantages. Pro Con “Boxes and arrows” Shows if electrons are paired or unpaired Longest method Spectroscopic notation Quicker than “Boxes and arrows” Does not show pairing of electrons Does not show core electrons Noble Gas notation Allows focus on the valence electrons (that control bonding) Quickest method Does not show pairing of electrons 44/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 22
- 23. AP Chemistry Rapid Learning Series - 12 Exceptions to the Aufbau Rule 45/60 Stability of d Subshells with 5 or 10 d subshells have 5 orbitals… They can hold 10 electrons. According to the Aufbau principle, Cr should have the following valence electron configuration: 4s2 3d4 But a half-full or completely full d subshell is more stable than the above configuration, so it is: 4s1 3d5 46/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 23
- 24. AP Chemistry Rapid Learning Series - 12 Elements with Exceptions The following elements are excepts to the Aufbau Principle: Element Should be Actually is Cr 4s2 3d4 4s1 3d5 Mo 5s2 4d4 5s1 4d5 W 6s2 5d4 6s1 5d5 Cu 4s2 3d9 4s1 3d10 Ag g 5s2 4d9 5s1 4d10 Au 6s2 5d9 6s1 5d10 They are the two groups on the periodic table that begin with Cr and Cu. 47/60 Quantum Numbers 48/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 24
- 25. AP Chemistry Rapid Learning Series - 12 Definition: Quantum Numbers Quantum Numbers – A set of 4 numbers that describes the electron’s placement in the atom. 49/60 4 Quantum Numbers ml n 2, 1, -1, + ½ l Quantum Number ms Symbol Describes Possible Numbers Principal n Shell number Whole #s ≥ 1 Azimuthal l Subshell S b h ll type Whole # < n Magnetic ml Orbital Spin ms Spin -l +l + ½ or – ½ 50/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 25
- 26. AP Chemistry Rapid Learning Series - 12 Determining Quantum Numbers 4p 3 n: principal energy level Give the number of the shell l: subshell s=0 p=1 d=2 f=3 coding system ml: orbital s 0 p -1 0 Number-line system of identifying orbitals. 0 is always in the middle. Number line from – l to + l 1 f d -3 -2 -2 -1 0 1 2 -1 0 1 2 3 ↑= + ½ ↓=-½ ms: spin Coding system 51/60 Quantum Number Examples Example: Give the quantum numbers for the red arrow. 1s 2s 2p 3s 3p 0 It s It’s in level “3” 3 It’s in subshell “s”—the “code” for “s” is “0” It’s in orbital “0” ___, ___, ___, ___ 3 0 0 -½ It’s a down arrow Example: Give the quantum numbers for the red arrow. 1s 2s It’s in level “2” 2p 3s -1 3p 0 +1 It’s in subshell “p”—the “code” for “p” is “1” It’s in orbital “-1” It’s an up arrow ___, ___, ___, ___ 2 1 -1 + ½ 52/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 26
- 27. AP Chemistry Rapid Learning Series - 12 Identifying Incorrect Quantum Numbers Example: What’s wrong with the following sets of quantum numbers? 1, 1, 0, + ½ 2, 1, -2, - ½ n = 2…OK as n can be any whole # >0 l = 1…subshell is “p” OK as level 2 has “p” ml = -2…on the “-2” orbital “p” subshell has 3 orbitals: ___ ___ ___ -1 0 +1 No “-2” orbital in a “p” subshell. ml must be between –l and l l 1, 0, 0, -1 53/60 n = 1…OK as n (energy level) can be any whole # > 0 l = 1…subshell is “p” There is no p subshell in energy level 1 n = 1…OK as n can be any whole # >0 l = 0…subshell is “s” OK as level 1 has an “s” ml = 0…on the “0” orbital OK as “s” has 1 orbital and it’s “0” ms = -1 ms must be either + ½ or – ½ Atomic Structure & The AP Exam 54/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 27
- 28. AP Chemistry Rapid Learning Series - 12 Atomic Structure in the Exam Common atomic structure problems: How many paired or unpaired electrons are in an atom of an element? t f l t? Given a set of quantum numbers, what’s the next higher level or sublevel? When shown a set of boxes & arrows, which element is it? Is a set of quantum numbers possible? This topic isn’t used in the Free Response section very often…usually just the multiple choice! 55/60 Multiple Choice Questions The first few questions on the AP MC exam give a list of choices and then ask several questions about that same list. Example: A. B. C. D. E. Se Mg Al N F 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p4 1s2 2s2 2p6 3s2 1s2 2s2 2p6 3s2 3p1 1s2 2s2 2p3 1s2 2s2 2p5 1. The atom that contains exactly 2 unpaired electrons A. Se (4 e-1 in the p subshell means 2 are unpaired) 2. The atom that contains exactly 2 electrons in the highest occupied subshell B. Mg 3. The atom that must obtain 3 electrons to obtain a full subshell 56/60 D. N (if a p has 3, it needs 3 more to be full) © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 28
- 29. AP Chemistry Rapid Learning Series - 12 Another Multiple Choice Question Example: Which of the following atoms is in an excited state? A. B. B C. D. E. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p4 1s2 2s2 2p6 3s2 3p2 1s2 2s2 2p6 3s2 3p2 4s1 1s2 2s2 2p6 3s2 3p6 4s2 3d8 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 An atom in an excited state is one in which an electron has been p promoted to a higher subshell. g Option “C” has an electrons in the 4s subshell when the 3p isn’t full—this shows a promoted electron. Answer: C 57/60 Learning Summary Electron configurations can be shown with boxes and arrows, in spectroscopic notation, or noble gas notation. Atoms are made of protons, neutrons and electrons. The configuration of the g electrons determines the chemical properties of the atom. Electrons are organized in levels, subshells and orbitals. Quantum numbers describe the ocat o o a location of an electron in an atom and are a series of 4 numbers. Electron configurations g are written following the Aufbau principle, Hund’s Rule and the Pauli Exclusion Principle. 58/60 © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 29
- 30. AP Chemistry Rapid Learning Series - 12 Congratulations You have successfully completed the core tutorial Atomic Structure and Electron Configuration Rapid Learning Center 59/60 Rapid Learning Center Chemistry :: Biology :: Physics :: Math What’s N t Wh t’ Next … Step 1: Concepts – Core Tutorial (Just Completed) Step 2: Practice – Interactive Problem Drill Step 3: Recap – Super Review Cheat Sheet Go for it! 60/60 http://www.RapidLearningCenter.com © Rapid Learning Inc. All rights reserved. :: http://www.RapidLearningCenter.com 30