2. 1. Identify the three rules for filling e - in an electron configuration. Aufbau Principle: Electrons fill lowest energy levels 1 st. An orbital can only hold two e - and they must have opposite spin. Pauli Exclusion Principle: Hund’s Rule: Sublevels with multiple orbitals (p, d, f) must fill orbitals one at a time before doubling up. p Chemistry Practice Test (Unit 2)

3. 1s2s2p Oxygen Z=8 Orbital Diagram: e - configuration: 1s 2 2s 2 2p 4 Dot Structure: Shows valence electrons (e - in highest energy level) as dots around the chemical symbol. O Valence Shell Each pair of dots represents a set of arrows (electrons with opposite spin) 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i

4. Nickel Z = 28 B) electron  configuration A) orbital  diagram C)Dot diagram 1s2s2p3s 3d 3p4s 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i 1s 2 2p 6 2s 2 3s 2 3p 6 4s 2 3d 8 Ni 4s 2 Ni or

5. 4.What is the frequency of light that has a wavelength of 405 nanometers. = c Knowns and unknown c = 3.00 x 10 8 m/s ν = ______________ λ = ______________ wavelength so this is 405 x 10 -9 m 405 x 10 -9 m = 3.00 x 10 8 m/s 405 x 10 -9 m = 7.41 x 10 14 1/s nano nano = 10 -9 405 What color is the light? c =

6. Types of electromagnetic radiation: 400 nm500 nm 600 nm 700 nm Wavelengths of visible light 405 nm

7. c = 4.What is the frequency of light that has a wavelength of 405 nanometers. wavelength nano 405 What color is the light? 405 nm is a darker shade of Blue light like indigo or violet.

8. Knowns and unknown h = 6.626 x 10 -34 J/Hz ν = ______________ E = ______________ 1.5 x 10 17 Hz E= (6.626 x 10 -34 J/Hz)(1.5 x 10 17 Hz) E = h E= 9.94 x 10 -17 J 5. What is the energy of a photon of X-Ray radiation with a frequency of 1.5 x 10 17 Hz? 1.5 x 10 17 Hz

9. A tanning bed produces ultraviolet electromagnetic radiation with a wavelength of approximately 250 nanometers. Remember the following values may be needed for finding frequency and energy. The speed of light (c = 3.00 x 10 8 m/s) and Plank’s constant (h = 6.626 x 10 -34 Js). 6. What is the frequency of these waves? = c Knowns and unknown c = ν = ______________ λ = wavelength so this is 250 x 10 -9 m 250 x 10 -9 m = 3.00 x 10 8 m/s 250 x 10 -9 m = 1.2 x 10 15 1/s nano = 10 -9 250 nanometers 3.00 x 10 8 m/s c =

10. 7. What is the energy associated with the ultraviolet light from the tanning bed? Knowns and unknown h = ν = E = ______________ 1.2 x 10 15 1/s = 1.2 x 10 15 1/s 6.626 x 10 -34 Js E= (6.626 x 10 -34 Js)(1.2 x 10 15 1/s) E = h E= 7.95 x 10 -19 J From previous problem