Review Material for Exam #3. 1. Radio waves for Rocket 101 are emitted at a frequency of MHz. Calculate the wavelength, in m, of this radiation.

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1 Review Material for xam #3 1. Radio waves for Rocket 101 are emitted at a frequency of Mz. alculate the wavelength, in m, of this radiation. 8 c.9979 x 10 m/s.971 m 6 1 ν x 10 s λν = c; λ = = =. The green line in the atomic spectrum of thallium has a wavelength of 535 nm. alculate the energy of a photon of this light hc (6.66 x 10 J s)(.9979 x 10 m/s) 7 Δ = hν = = = λ 5.35 x 10 m 3.71 x 10 J 3. Light with a wavelength of 465 nm lies in the blue region of the visible spectrum. alculate the frequency of this light. What is the energy associated with this wavelength? 8 c.9979 x 10 m/s λν = c; ν = = = 7 λ 4.65 x 10 m x 10 s = hν = 6.66 x 10 J s x 6.45 x 10 s = 4.7 x 10 J/photon 4. An electron in the 5 th energy level of Be 3 goes down to the first level. alculate: a. The change in energy (J) of the electron. b. The frequency of light emitted (s 1 ). c. The wavelength of light emitted, in m and nm..18 x = = x 10 J 5.18 x = = x 10 J 1 18 Δ = 1 5 = x 10 J ( x 10 J) = 3.35 x 10 J (emitted) Δ x 10 J Δ = hν; ν = = = x 10 s 34 h 6.66 x 10 J s 34 8 hc hc (6.66 x 10 J s)(.9979 x 10 m/s) 9 Δ = hν = ; λ = = = 5.93 x 10 m λ Δ x 10 J nm 5.93 x 10 m x = 5.93 nm 1 m

2 5. alculate the frequency of electromagnetic radiation emitted by the hydrogen atom in the electron transition from n = 4 to n = 3. What is the wavelength (in nm) emitted?.18 x = = x 10 J.18 x = =.4 x 10 J Δ = 3 4 =.4 x 10 J ( x 10 J) = x 10 J (emitted) Δ x 10 J Δ = hν; ν = = = 34 h 6.66 x 10 J s x 10 s 34 8 hc hc (6.66 x 10 J s)(.9979 x 10 m/s) 6 Δ = hν = ; λ = = = 1.87 x 10 m λ Δ x 10 J nm 1.87 x 10 m x = 1 m 1870 nm 6. State whether the following are valid sets of quantum numbers and if not why: n l m l m s a / yes, s _ b / no, l has values to n 1. n = 0; l can only be 0 c. 3 1/ yes, 3d d / yes, p e / no, m l has values to -l to l. 0 only allowed value f / no, m l has values from -l to l. ± max for l =. g / no, n is integers

3 7. Draw the shapes (including the orientation) of all the s, p and d orbitals. s z x y y z z x y x p z p x p y d xy d xz d yz d x y d z 8. Give the ground state electron configuration for the following: S 1s s p 6 3s 3p 6 Te 1s s p 6 3s 3p 6 4s 3d 10 4p 6 5s 4d 10 5p _ _ _ V 5 1s s p 6 3s 3p 6 Nb 1s s p 6 3s 3p 6 4s 3d 10 4p 6 5s 4d _ _ u 1s s p 6 3s 3p 6 4s _3d 10 Zn 1s s p 6 3s 3p 6 4s _3d 10 l 1s s p 6 3s 3p 6 Ba 1s s p 6 3s 3p 6 4s 3d 10 4p 6 5s 4d 10 5p 6 6s Re 1s s p 6 3s 3p 6 4s 3d 10 4p 6 5s 4d 10 5p 6 6s 4f 14 5d _ _ _ _ _ F 1s s p _ As 3 1s s p 6 3s 3p 6 4s 3d 10 4p 6 r 1s s p 6 3s 3p 6 4s _3d _ _ _ _ _ 9. What is the atomic number and the complete electron configuration of the yet undiscovered element directly below Fr in the periodic table? 119 1s s p 6 3s 3p 6 4s 3d 10 4p 6 5s 4d 10 5p 6 6s 4f 14 5d 10 6p 6 7s 5f 14 6d 10 7p 6 8s _

4 10. Which of the following atoms, Na, Mg, S, or K has the a. smallest atomic radius S b. lowest ionization energy K 11. Which of the following atoms, a, As, Br, or Rb has the a. largest atomic radius Rb b. highest ionization energy Br 1. Which of the following are larger than an N atom? a. N 3 b. N 5 c. O d. e. P 13. On the basis of their position on the periodic table, select the atom with the larger atomic radius in each of the following pairs: a. Na, s e. Ne, Xe b. Be, Ba f. Na, P c. N, Sb g. K, Ge d. F, Br h. Al, l 14. xplain why it is unusual for I 1 of S to be lower then I 1 of P. Give a possible explanation. S is smaller than P, I should increase going across a row. The reason is found in e configuration: 1s s p 6 3s 3p _ _ becomes 1s s p 6 3s 3p _ _ _. Being halffilled, it has a bit more stability. P, on the other hand, starts as 1s s p 6 3s 3p _ _ _ and loses the stability when it becomes 1s s p 6 3s 3p _. 15. Identify each ion: a. 3 ion: 1s s p 6 Al 3 b. 3 ion: 1s s p 6 3s 3p 6 3d 3 r 3 c. ion: 1s s p 6 3s 3p 6 4s 3d 10 4p 6 5s 4d 10 Sn d. ion: 1s s p 6 3s 3p 6 4s 3d 10 4p 6 Se 16. Write the reaction of each of the oxides with water: K O, MgO, P O 5, SO, O. K O O KO base MgO O Mg(O) base P O 5 3 O 3 PO 4 acid SO O SO 3 acid O O O 3 acid

5 17. Use a Born-aber ycle to calculate the missing energy (bold) of the following: a. Δ o f BeI (s) 08 kj/mole BeI sublimation Be(s) 30 kj/mole Be(g) I kj/mole I 1757 kj/mole dissociation I (s) 107 kj/mole I A I(g) 95 kj/mole lattice BeI (s) 794 kj/mole BeI 08 kj Be(s) I (s) BeI (s) 30 kj (107 kj) Be(g) I(g)? kj 903 kj 1757 kj ( 95 kj) Be (g) I (g) 08 kj = 30 kj 660 kj (107 kj) (95 kj) lattice lattice = 794 kj b. Li(g) Li (g) e = 540 kj/mole Li(s) Li(g) sublimation = 16 kj/mole 1/ O (g) O(g) dissociation = 44 kj/mole O O(g) e O (g) = 598 kj/mole Li (g) O (g) Li O(s) lattice = 800 kj/mole Li O Li(s) 1/ O (g) Li O(s) f º = 554 kj/mole Li O 554 kj Li(s) 1/ O (g) Li O(s) (16 kj)? kj Li(g) O(g) 800 kj (540 kj) 598 kj Li (g) O (g) 554 kj = (16 kj) (540 kj) diss 598 kj 800 kj dissociation = 44 kj

6 c. Δ o f MnS(s) 1 kj/mole MnS sublimation Mn(s) 4 kj/mole Mn(g) I 1 71 kj/mole I 1509 kj/mole sublimation S(s) 64 kj S(g) A 1 00 kj/mole A 446 kj/mole lattice MnS(s) 3176 kj/mole MnS 1 kj Mn(s) S(s) MnS(s)? kj 64 kj Mn(g) S(g) 3176 kj kj kj Mn (g) S (g) 1 kj = sub 30 kj 64 kj 46 kj 3176 kj; sub 4 kj/mole d. Δ o f Th S 3 (s) 77 kj/mole (see me for work) sublimation Th(s) 58 kj/mole Th(g) I kj/mole I 1110 kj/mole I kj/mole I kj/mole dissociation S 8 (s) 79 kj/mole S S(g) A 1 00 kj/mole A 589 kj/mole lattice Th S 3 (s) kj/mole 18. Draw the best Lewis structure of each of the following. Include all lone-pair electrons and non-zero formal charges on each atom: l 4 1 x (4 e ) 4 e l 4 x l (7 e ) 8 e 3 e l l l P 3 1 x P (5 e ) 5 e 3 x (1 e ) 3 e 8 e P

7 O 3 3 x O (6 e ) 18 e 18 e O O O _ NO 3 O 1 x N (5 e ) 5 e 3 x O (6 e ) 18 e 1 e 4 e x (1 e ) e 1 x (4 e ) 4 e 1 x O (6 e ) 6 e 1 e O N O _ O _ O 4 x (4 e ) 8 e 4 x (1 e ) 4 e 1 e N SiF 4 N N 4 x N (5 e ) 10 e 10 e 1 x Si (4 e ) 4 e 4 x F (7 e ) 8 e 3 e 1 x (1 e ) 1 e 1 x (4 e ) 4 e 1 x N (5 e ) 5 e 10 e 1 x N (5 e ) 5 e 4 x (1 e ) 4 e e 8 e F N N F Si F F N N