1. Agenda Midterm – October 26 th / 27th Chapter 5 Quiz – October 21 Formal Lab – October 21 st Homework (wb 5) – October 24/25th 

2. Light Electromagnetic radiation – Form of energy that exhibits wavelike behavior Terms to know – Wavelength Measured from crest to crest (measured in meters, m) – Amplitude A waves height

4. – Frequency Number of waves that pass a given point Low frequency High frequency

5. The speed of Light C is a given = 3.00 x 10 8 m/s λ = wavelength (meters, m) ν = frequency (Herts, Hz = waves per second)

6. Answer the following questions pg 121 What is the frequency of a green light, which has a wavelength of 4.90 x 10 -7 m? An X ray has a wavelength of 1.15 x 10 -10 m? What is the speed of an electromagnetic wave that has a frequency of 7.8 x 10 -6 Hz A popular radio station broadcast with a frequency of 94.7 MHz What is the wavelength of the broadcast? (1MHz = 10 6 Hz)

7. Particle nature of Light Quantum = minimum amount of energy that can be gained or lost by an atom The energy of a quantum is related to the frequency of the emitted radiation

9. Planck’s Constant E quantum = hν – H = 6.626 x 10 -34 J(s) – ν = frequency measure per second

10. Answer the following Question pg 124 What is the energy of each of the following types of radiation? – A 6.32 x 10 20 s -1 – b. 9.50 x 10 13 Hz – c. 1.05 x 10 16 s -1

12. Answer the questions on page 147 #s 65-76

14. N - 1 N - 5 N - 4 N - 2 N - 3 N - 5

15. Bohr Model of the Atom A single electron moves around the nucleus in only certain allowed circular orbits. Each orbit has an energy level – Larger the orbit…larger the energy level “n” = the quantum number – This the orbit and the corresponding energy level.

16. 16 Bohr’s Model of the atom The larger the orbital, the further the e- are from the nucleus + n = 1 n = 2 n = 3 n = 4 Quantum # (n)-Indicated energy level or orbital The probability of finding e - in certain regions of an atom is described by an orbital Orbitals have characteristic shapes, size and energies, but do NOT tell how e - move Neils Bohr

17. Energy Levels N-1 S orbital only…2 electrons N-2 S orbital…P orbital…6 electrons N-3 S & P orbital N-4 S…3d orbital (10 electrons)…P N-5 S…4d orbital (10 electrons)…P N-6 S…5d orbital (10 electrons)…4f orbital (14 electrons)…P N-7 S…6d orbital (10 electrons)…5f orbital (14 electrons)…P

18. Quantum model 18

19. Each Orbital has energy levels

20. Ground State Electron Configurations Aufbau principle…each electron occupies the lowest energy orbital available. Pauli exclusion principle – 2 electrons occupy a single orbital – Each electron has an opposite spin Hund’s rule – Single electrons with the same spin must occupy each equal energy orbital before additional electrons with opposite spins can occupy the same orbitals. Pg 136

21. Aufbau Principle Each electron occupies the lowest energy orbital available

22. Pauli’s Exclusion Principle

24. Hund’s Rule Single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins can occupy same orbitals

25. Hund’s Rule

27. The Orbitals

28. Orbital diagrams

29. Noble Gas Notation

30. 30 Electron Spin - e- spin either clockwise or counterclockwise which creates a magnetic field Pauli Exclusion Principle – - an orbital with 2e- of opposite spin are said to have a pair of e- Sublevels# Orbitals Max # of e- s 1 2 p 3 6 d 5 10 f 7 14 Figure 4-24 each orbital in an atom can hold up to 2e- that must have opposite spin (  and  )

31. 31 Electron Configurations Definition Distribution of e- among orbitals; describes where e- are and what energy they have Aufbau Principle – Hund Rule – _____ _____ _____ _____ _____ 1s 2s 2p x 2p y 2p z 1s 2 2s 2 2p 6  e- are added one at a time to the lowest energy level available e- occupy equal energy orbitals so the maximum number of unpaired e- result

32. 1s 2 2s 2 2p 6 Orbital Last level of energy Number of electrons in a particular orbital Level of energy This particular atoms has 2 levels of energy 10 electron total 2 + 2 +6 8 electrons in the last level of energy 2 +6 32

33. 33 How To Do Energy Diagrams Step 1 Step 2 Step 3 Step 4 Determine atomic number Determine number of e- - if neutral: # e- = atomic # - if ion: # e- = atomic # - charge Fill in atomic orbital energy diagram using following principles - Pauli: 2e- max per orbital with opposite spin - Aufbau: 1e- at a time filling lowest energy levels first - Hund: max # of unpaired e- Determine number of paired and unpaired e- Step 5Write e- configuration

34. 34 ExampleDetermine the e- configuration of Ne by using an atomic orbital energy diagram 3s _____ 2p _____ _____ _____ 2s _____ 1s _____         Atomic # = 10 # e- = 10 – 0 = 10 Paired = 5 Unpaired = 0 e- config: 1s 2 2s 2 2p 6 ExampleDetermine the e- configuration of S by using an atomic orbital energy diagram 4s _____ 3p _____ _____ _____ 3s _____ 2p _____ _____ _____ 2s _____ 1s _____        Atomic # = 16 # e- = 16 – 0 = 16 Paired = 7 Unpaired = 2 e- config: 1s 2 2s 2 2p 6 3s 2 3p 4     

35. 35 ExampleDetermine the e- configuration of Fe + by using an atomic orbital energy diagram 3d _____ _____ _____ _____ _____ 4s _____ 3p _____ _____ _____ 3s _____ 2p _____ _____ _____ 2s _____ 1s _____     Atomic # = 26 # e- = 26 – 1 = 25 Paired = 10 Unpaired = 5 e- config: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 5             ExampleDetermine the e- configuration of F - by using an atomic orbital energy diagram 3s _____ 2p _____ _____ _____ 2s _____ 1s _____ Atomic # = 9 # e- = 9 – - 1 = 10 Paired = 5 Unpaired = 0         e- config: 1s 2 2s 2 2p 6

36. 36 Start with 1s and read up the arrow Order of Energy Levels from Lowest (1s) to Highest Group 1 – Alkali Metals Group 2 – Alkaline Earth Metals Group 1- 10 – Transition Metals Group 5 – Nitrogen Group Group 8 – Nobel Gas Group 3 – Boron Group Group 4 – Carbon Group Group 6 – Oxygen Group Group 7 – Halogens Period 4f– Lanthanides Period 5f– Actinides

38. Valence Electrons Only certain electrons can determine the chemical properties of an element – Valence Electrons Valence electrons are defined as electron’s in the atom’s outermost orbital…or highest energy level

39. Valence Electrons Steps to create Lewis Structures for single elements – Find the number of electrons in the last S and P orbitals…or look on the chart to find the number of valence electrons on the periodic table – Arrange electrons around Element symbol evenly – Ex: Chlorine 7 Valence Electrons Cl

40. Valence Electrons

41. Electrons in the atom’s most outer orbitals – The electrons in the last S and P orbitals Boron – 1s 2 2s 2 2p 1 Iodine – 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 5 Electron Dot… HCOHe LiPFAr