Mixon CH131_W2005
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Exam 2B
Table O’Information
Solubility:
All common compounds of Group I and ammonium ions are soluble.
All nitrates , acetates, and chlorates are soluble.
All binary compounds of the halogens Group VIIA (other than F) with metals are soluble,
except those of silver, mercury (I), and lead.
All sulfates are soluble, except those of barium, strontium, calcium, lead, silver, and mercury
(I). The latter three are slightly soluble.
Except for rule 1, carbonates, hydroxides, oxides, silicates, and phosphates are insoluble.
Sulfides are insoluble except for calcium, barium, strontium, magnesium, sodium,
potassium, and ammonium.
 1
1
E = -2.179 x 10-18J  2  2
nL
 nH
E = h




h =6.626 x 10-34 Js
c = 
=
h
mv
c = 2.9979 x 108 m/sec
 1
1
1
 R 2  2

λ
n2
 n1




NA = 6.022 x 1023
R = 1.0968 x 107 m-1
M1V1 = M2V2
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Mixon CH131_W2005
Exam 2B
Name:_______________________________________________________ Date:_________________
EXAM 2B
1.)
A 20.00 mL sample of an aqueous solution of magnesium hydroxide requires 43.30 mL of
0.1200 M HNO3 (aq) for its neutralization, what is the molarity of Mg(OH)2 (aq)? (4.5 pts)
2HNO3 (aq) + Mg(OH)2(aq) → 2H2O(l) + Mg(NO3)2 (aq)
2.)
In the following reaction, indicate the oxidation numbers of each species, identify and
label the species being oxidized, the species being reduced, the oxidizing agent, and the
reducing agent and write the half-reactions: (9 pts)
FeCl3 (aq) + H2S (aq)  FeS(s) + S(s) + HCl(aq)
Fe:
→
Fe:
Cl:
→
S:
H:
→
S:
S:
→
H:
Cl:
Oxidation half-reaction:
Reduction half-reaction:
Species oxidized:______________
Species reduced:_____________
Oxidizing agent:_______________
Reducing Agent:________________
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Mixon CH131_W2005
3.)
Exam 2B
Complete the following chemical reactions and balance each. Predict whether a
precipitation reaction will occur in each of the following cases. IF (and only if) a
precipitate forms, write the ionic and net-ionic equations: (8 pts)
a.) ______Pb(NO3)2 (
)
+ ______(NH4)2CO3 (
)
→
ionic:
net-ionic:
b.) ______KCl (
)
+ ______Na3PO4
(
)
→
ionic:
net-ionic:
c.) ______CaSO4 (
)
+ ______KOH (
)
→
ionic:
net-ionic:
4.)
Write/list all the components in the visible spectrum in order with the LARGEST
(highest) frequency on the left and the SMALLEST (lowest) frequency on the right (3 pts)
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Mixon CH131_W2005
Exam 2B
5.) You work for a lab that converts cyclohexane(C6H12) to adipic acid (H2C6H8O4) using the
following reaction:
____C6H12(l) + ____O2(g)  ____H2C6H8O4(l) + ____H2O(g)
You use 22.63 g of C6H12, 45.42 g of O2, and end up producing 11.85 g of H2C6H8O4. Determine
the theoretical yield and the percent yield of adipic acid. (8 pts)
6.)
Name the following: (8 pts)
a.) Co(NO3)2
b.) CrPO4
c.) Zn(CH3COO)2
d.) H2SO4 (aq)
7.)
You are in lab trying to make a 150.0mL sulfuric acid solution. If you have 35.00mL of a
4.268M stock solution then what is the concentration of the solution you made? (3 pts)
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Mixon CH131_W2005
Exam 2B
8.) Calculate the energy, wavelength, and frequency for a transition that occurs when an
electron falls from the n=6 to the n=3 level (BONUS 2 pts: who is this transition named
after and what region of the EM spectrum does it correspond to?) (5 pts)
9.)
Calculate and indicate which species is more energetic: red light (wavelength = 725 nm)
or yellow light (595 nm) (5 pts)
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Mixon CH131_W2005
Exam 2B
10.) A analysis of nicotine, a poisonous compound found in tobacco leaves, shows that it is
74.5% C, 8.65% H, and 17.25% N. Its molar mass is 162 g/mol. Determine its (a)
empirical and (b) molecular formulas? You must show how you determine the molecular
formula as well as the empirical formula. (8 pts)
11.) Explain what is meant by energy being quantized and why there are certain lines in an
emission spectrum (e.g. the spectrum is not continuous) (3 pts)
12.) State the Heisenberg Uncertainty principle? (2 pts)
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Mixon CH131_W2005
Exam 2B
13.) Give the three reasons why the Bohr model could not predict spectral lines for atoms
other than Hydrogen? (3 pts)
14.) Calculate the de Broglie wavelength of a 0.422-g frozen pea shot through a blow gun at a
velocity of 6.21 x 102 mm/s. (3 pts) HINT: 1J = 1kgm2/sec2
15.) Write the complete (no noble gas shorthand!!) for the following elements/ions (6 pts)
a) Mn
b) S
c) Zn
d) Mn+2
e) S-2
f) Zn+2
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Mixon CH131_W2005
Exam 2B
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16.) Write the electron configuration for Zn and Zn . Draw all the orbital boxes for the
neutral atom. Be sure to label the orbital boxes that you draw! Write the complete set of
quantum numbers for electrons 4, 19, 20, and 28 in the neutral atom. (10 pts)
17.) Put the following in order of increasing size. Put the smallest species on the LEFT and
then arrange them in order of increasing size with the largest species on the RIGHT:
Be+2, O-2, Li+1, B+3, N-3, F-1. (3 pts)
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Mixon CH131_W2005
Exam 2B
18.) Indicate whether or not the following quantum numbers are valid, if there is an error,
write a valid set of quantum numbers keeping n and ml constant: (3.5 pts)
a. n= 4 l = 6 ml = 2
b. n= 5 l = 2 ml = -3
c. n= 2 l = 1 ml = -1
d. n= 3 l = 3 ml = -2
BONUS: Explain how light can be thought of as a wave: give a specific reason!
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