Name __________________________________________Gen Chem I Lecture

Exam 4

5DEC97

Dr. L. J. Rivela

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1. YOU MUST SHOW ALL EQUATIONS, LOGIC, AND CALCULATIONS IN ORDER TO RECEIVE ANY CREDIT !
2. ALL NUMERICAL ANSWERS MUST HAVE THE PROPER NUMBER OF SIGNIFICANT FIGURES AND BE
                   EXPRESSED IN SCIENTIFIC NOTATION WHERE NECESSARY.
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1.	On the coordinates provided below, please draw the shapes of the s, p, and d orbitals [contour diagrams]. Indicate the name of the specific orbitals drawn on the space below the orbital and indicate on the diagram the appropriate sign of the wave function. [18]

2.	Please supply the following information with respect to Quantum Numbers: [8]

	[a]	What is the selection rule for n ?	______________________________________
	[b]	If n = 3, what values could l have ?	______________________________________
	[c]	If l =2, what values could ml have ?	______________________________________
	[d]	What does ms indicate about an electron ?	______________________________________

3.	Write the electronic configurations for the following species, according to Aufbau. Do not use shorthand notation. [9]

	[a]	97[ Bk]
	[b]	38 [Sr] 2+
	[c]	7 [N] 3-

4.	Write the orbital block diagram for 14 Si . . . [8]

5.	Write the four quantum numbers associated with the outermost electrons in 14 Si . . . . [8]

6.	Circle g.s. [ground state]; e.s. [excited state]; or i [incorrect]

                 

7.	A compound used in sun screens, p-aminobenzoic acid [called PABA] absorbs ultraviolet radiation with maximum absorption occurring at 265 nm. Calculate the frequency associated with this radiation . [6]

8.	Calculate the frequency of a photon emitted during a transition from the n = 8 state to the n = 4 state in the [Lithium] 2+ cation ? [10]

9.	Write the electronic configurations for the following species, you may use shorthand notation. [6]

	[a]	29[ Cu]
	[b]	45 [Rh] 3+

10.	Please define 5 [FIVE] of the following terms in SHORT, CONCISE STATEMENTS. [20]

Draw a line through the term not defined and please write clearly.

	[1]	Balmer Series
	[2]	Pauli Exclusion Principle
	[3]	Bohr's Quantizing condition
	[4]	Heisenberg Uncertainty Principle
	[5]	Hund's rules
	[6]	paramagnetic
	[7]	quantization of energies

11.	The fastest serve in tennis is about 140 miles per hour, or 62 m/s. Calculate the wave length associated with a 60.0 g tennis ball, in "SI" units, traveling at this speed. [8]

12.	Explain clearly, with the use of electronic configurations, how the reaction of Aluminum metal with oxygen gas leads to the formation of the salt : Aluminum oxide. Describe the type of bonding which Al2O3 exhibits. [10]

13.	Please circle the atom with the GREATER : [8]

	[a]	ionization potential Ge or Mg	[c]	metallic character Fe or Cr
	[b]	electron affinity As or N	[d]	electronegativity Ca or Ba

14.	Draw the LEWIS electron dot structures expected for SO3 [10]

15.	Draw the LEWIS electron dot structure expected for [NO] + [8]

16.	On the coordinates provided, draw two atomic orbitals overlapping to form a sigma bond and two atomic orbitals overlapping form pi bond. Please label your diagrams completely and give a definition of each type of bond. [14]

17.

M A T C H I N G: [22]

	[a]	Choice items [A to S] may be used ONCE, MORE THAN ONCE, OR NOT AT ALL !
	[b]	Note: there may be more than one answer to a given question.
	[c]	Place the appropriate letter (s) in the spaces provided.

	___________	[1]	ionic compound
	___________	[2]	halogen
	___________	[3]	periodic trend that increases from bottom to top and left to right
	___________	[4]	valence shell which consists of the filling of an inner orbital
	___________	[5]	atoms or ions which have the same electronic configuration
	___________	[6]	the properties of the elements are periodic functions of their atomic numbers.

	[a]	metallic character	[h]	alkaline earth metals	[o]	electron affinity
	[b]	alkali metals	[i]	iodine	[p]	resonance
	[c]	transition metals	[j]	KBr	[q]	size
	[d]	the periodic law	[k]	isoelectronic	[r]	CaF2
	[e]	fluorine	[l]	wavelength	[s]	lanthanides
	[f]	actinides	[m]	ionization potential	[t]	covalent bonding
	[g]	water	[n]	bubble gum

Extra Credit . . . if you like

The size of the phosphorous atom (atomic radius = 1.10 Å) is smaller than that of the aluminum atom (atomic radius = 1.43 Å) ! Please give a clear theoretical explanation of these facts. [9]

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DATA:	c = 3 . 00 x 10 8 m/s	1 m = 1 x 10 9 nm
	B = 2 . 179 x 10 -18 J	S H2O = 4 . 184 J/g·C

Total points = 185

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