Exam I Spots A
Use to study but do not memorize problems! Also review examples in class, problem sets, and extra problems
1. Complete the following table: (use full atomic symbols including any charges) (20 pts)
Full symbol
78
Se2-
_______
# protons
# neutrons
# electrons
charge
_______
_______
_______
_______
_______
105
69
3+
2.
Write either the formula or name for the following compounds. (20 pts)
(a)
P2Br4
(b)
Mn2O3
(c)
Strontium Iodide
(d)
Aluminum Sulfide
(e)
Iron (II) bromate
3.
The containers for the following chemicals have lost their labels. (20 pts)
Ti(NO3)2
PBr5
NH4Cl
PH3
Help the Chemistry Department’s dedicated laboratory assistants re-label the containers using the
compounds listed above.
Container
Description
Chemical Formula (from above)
A
white crystalline solid
___________
B
colorless gas
___________
C
violet powder
___________
D
colorless liquid
___________
1.
2
Write either the formula or name for the following compounds.
(a)
Calcium Nitrate
(b)
FeCO3
(c)
tetraphosphorous hexoxide
(d)
AgClO4
2. Complete the following table: (use full atomic symbols including any charges)
symbol
53
Cr
_______
3.
# protons
# neutrons
# electrons
charge
_______
_______
_______
_______
_______
125
80
3+
The containers for the following chemicals have lost their labels.
NH4NO3
CH3CH2CH2OH
CrCl3
NO2
Help the Chemistry Departments dedicated laboratory assistants re-label the containers.
Container
Description
Chemical Formula
A
brown gas
___________
B
white crystalline solid
___________
C
purple powder
___________
D
colorless liquid
___________
3
4. Provide brief answers for the following questions. (30 pts)
(a) Predict what is the most abundant isotope of Platinum (Pt) and write the full atomic symbol for its 2+ ion?
(b) What species are formed when CsClO4 is dissolved in water? Will this solution be colorless?
(c) Write the shorthand electron configuration for a W4+ ion?
(d)
What 1- ion has the same ground state valence electron configuration as Ne?
(e) Using the appropriate coordinate system, sketch a 4dxy orbital and indicate the location of any planar nodes
(f) Identify an anion that has the following exited state electron configuration
1s22s22p63s23p64s23d104p45s2
4
4. Provide brief answers for the following questions.
(a) How many significant figures are in 100410 mg Tc?
(b) What species are formed when Na3PO4 is dissolved in water?
(c) What is the most abundant isotope of Selenium (Se)? Write the full atomic symbol.
(d) Eureka, you have just discovered a new element with 115 protons and 174 neutrons. Granted it only exists
for 10 milliseconds but its existence was confirmed. What element will its chemistry most closely
resemble?
(e) How many nucleons are present in the ion 114 Be2+?
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5. Give TWO EXAMPLES of the following: (15 pts)
TWO EXAMPLES
(b) Two solids containing Ba that will be colorless
(c) Two transition metal ions with 6 valence electrons
(f) Two orbitals that can have the quantum numbers l = 3 and ml = 0.
(d) ONE electron configurations that violate the Pauli Exclusion Principle
(6) In 2006, the Element 116 (give it the symbol X) had not been discovered and remains unknown. Identify the
following that would correspond to the hypothetical element 116, X. (15 pts)
(a) What group would Element X belong to?
(b) What period would Element X belong to?
(c) How many valence electrons would Element X have?
(d) What other element would be similar in chemistry to element X
(e) What would be the formula for the compound that it would form with Cesium, Cs?
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5. Provide brief answers for the following questions:
(a) Give examples of TWO likely isotopes of silver, Ag
(b) Give examples of TWO solids containing F that will be colorless
(c) Give examples of TWO Alkaline Earth ions
(d) Give TWO examples of colored salt?
6.
7
Consider the element Iodine (I), which is used by the human body to synthesize the hormones thyroxine
and triiodothyronine.
Circle all the following terms that apply to Iodine, I?
(1) gas
(2) non-metal
(3) metal
(4) metalloid
(5) similar to Cl
(6) similar to Xe
(7) s-block
(8) p-block
(9) d-block
(10) transition metal (11) similar to Te
(12) halogen
(13) chalcogen
(14) period 6
(16) alkali metal
(15) period 7
7.
8
Consider the process for boiling of dichlorine hexoxide
(a) Write out a chemical equation that describes/represents the boiling of dichlorine hexoxide
(7 pts)
(b)

(c)
Is this process expected to be endothermic, exothermic, or hypothermic (briefly explain) (5 pts)
Sketch a reaction profile (energy diagram) for the reaction in part (a). On your graph, be sure to (i) label
the axes, (ii) show the location of the reactants, products, and the change in enthalpy (8 pts)
8. Indium is a primary component of the compound, Indium Tin Oxide (ITO). ITO is used to make mainly
used to make transparent conductive coatings for liquid crystal displays, flat panel displays, plasma displays,
touch panels, and electronic ink applications.
(a) What group on the periodic table does Indium, In, appear in? (5 pts)
(b) Write the full electron configuration for Indium, In. (5 pts)
(c) Write the electron configuration for In using shorthand notation. (5 pts)
(d) Use an orbital diagram to show the ground state electron configuration for the valence electrons (5 pts)
(e) Use an orbital diagram to show an excited state electron configuration for the valence electrons. (5 pts)
(f) What element will have similar chemical properties as In? Briefly explain(5 pts)
7.
9
Consider the following reactions. Determine whether the reactions are exothermic or endothermic
(a)
CO2(g)
+
H2O (g)
H2 (g) -----→
+
CO(g)
H = 41.1 KJ/mol
(b)
C3H8 (g)
(c)
+ 5 O2 (g) -----→
4 H2O (g)
+ 3 CO2 (g)
Sketch a reaction profile (energy diagram) for the reaction in part (a). On your graph, be sure to (i) label
the axes, (ii) show the location of the reactants, products, and the change in enthalpy
8. Pure bismuth is a white, brittle metal with a slight pink color. Bismuth can occur free in nature and in such
minerals as bismuthinite (Bi S ) and bismite (Bi O ).
2
3
2
3
(a) What period on the periodic table does Bismuth appear in?
(a) Write the full electron configuration for Bismuth, Bi.
(c) Write the electron configuration for Bi using shorthand notation.
(d) Use an orbital diagram to show the ground state electron configuration for the valence electrons
(e) Use an orbital diagram to show an excited state electron configuration for the valence electrons.
(f) Is Bismuth paramagnetic or diamagnetic?
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9. Provide brief answers for the following questions.
(a) Order the following atoms/ions according to increasing size (smallest to largest)
Ca, B, Al, N, F, Sr, Mg
(b) Under what two conditions will a gas behave as though it were non-ideal?
(c) In an atom of phosphorous, P, how many electrons have the quantum number ml = 0
(d)
How many nodal planes are present in a 5s orbital of Ru?
(e) Using the appropriate coordinate system, sketch a 3pz orbital and show the location of the nodal plane?
(f) What is the ground state electron configuration of Re3+? (use shorthand notation)
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10. Give TWO EXAMPLES of the following:
TWO EXAMPLES
(a) TWO types of electromagnetic radiation with shorter wavelengths than blue light
(b) TWO elements with the same valence shell configuration as In, Indium
(c) TWO transition metal cations with 4 valence electrons
(d) TWO orbital configurations that do not obey the Pauli Exclusion Principle.
(e) TWO elements with a s2d3p3 excited state valence shell configuration
(f) TWO excited state configurations for Mg.
9.
12
Using Bohr’s model of the hydrogen atom, a photon with an energy of 5.3961 x 10-17 J is emitted when
an electron moves from an orbit with n = 5 to n = 2. (30 pts)
(a) Calculate the frequency of this photon. USE the CORRECT NUMBER of Significant Figures(15 pts)
(b) What is the wavelength (IN NM) of this emitted photon? (10 Pts)
(c) What TWO types of photon would have a longer wavelength that this photon of visible light?
(Give TWO type of electromagnetic radiation) (5 pts)
11.
13
The newest (and most expensive) laser pointers on the market emit green light with a wavelength of 532
nm, which is more in tune to the sensitivity of the human eye.
(a)
Determine the frequency of light emitted by this laser pointer
(b)
What is the energy (in joules) associated with a single photon of this green light?
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Useful Constants and Equations
Planck's constant
Speed of light
Atomic mass unit
Boltzmann constant
Gas Constant
h = 6.626 x 10-34 J•s
c = 2.9979 x 108 m/s
amu = 1.66054 x 10-27 kg
k = 1.38066 x 10-23 J / K
R = 8.31451 J / K mol
R = 0.08206 L • atm / K mol
E = 2.31 x 10-19 J • nm (q1 q2 / r)
zero order:
[A] = -kt + [A]0; t1/2 = [A]0/2k
(KE)avg = 3/2 RT
first order:
ln [A] = -kt + ln [A]0; t1/2 = ln 2/k
urms = (3RT / M)1/2
second order: [A]-1 = kt + [A]-1; t1/2 = 1/k[A]0
ln(P1/P2) = H/R (1/T2 – 1/T1)
k = Ae-Ea/RT
ln(k1/k2) = Ea/R (1/T2 – 1/T1)
-b ± b2 - 4ac
x=
2a
E = mc2
PMm = dRT
E = -2.178 x 10-18 J ((Z2/nfinal2) – (Z2/ninit2))