CAP Unit 03 Exam Study Booklet
This study booklet is to be completed AND corrected in entirety prior to taking the next unit exam
Activity
Complete the orbital viewer assignment and staple to your CAP Unit 03 Study Booklet. Note: you will need to modify your
work so that the software program information correlates with the text book information. The second quantum number “l”
refers to the s, p, d and f subshell and can be assigned the numbers 0, 1, 2, 3 respectively. In other words, the program
defines a sublevel with letters, whereas the text book defines them with a number. Therefore, your first text box in this
assignment should state “…in the s subshell (l=s aka l=0)...” orbital view key
Questions
1.
Balance and determine the IUPAC names for the following reaction: (NH4)2S (aq) + FeCl2
Furthermore, identify the precipitate and explain what the term mean.
a)
1(NH4)2S (aq)
+
1FeCl2 (aq)
b) ammonium sulfide
c)
2.
+
ammonium chloride
1FeS(s)
iron(II) sulfide
Write an overall balanced equation where aqueous lead(II) nitrate reacts with aqueous potassium hydroxide to produce
the precipitate lead(II) hydroxide and aqueous potassium nitrate.
+
2KOH (aq)

1Pb(OH)2 (s)
+
2KNO3 (aq)
Must include the
(s) and (aq)!
Ethane burns in oxygen to produce carbon dioxide and water. Write the balance equation for the reaction and
determine how many grams of carbon dioxide would be produced if 14.5 grams of ethane were consumed in the
presence of unlimited oxygen. Furthermore, determine the mass at which oxygen becomes the limiting factor.
a)
2C2H6 (g)
b) 14.5 g C2H6
c)
4.
iron(II) chloride
2NH4Cl (aq)
(aq) + FeS(s).
The precipitate is the solid iron(II) sulfide that was formed during the reaction that falls out of solution.
1Pb(NO3)2 (aq)
3.

4Cl
42.5 g CO2
+
7O2 (g)

4CO2 (g)
+
6H2O (l)
4 mol CO2
2 mol C2H6
44.0 g CO2
1 mol CO2
1 mol C2H6
30 g C2H6
42.5 g CO2
7 mol O2
4 mol CO2
32.0 g O2
1 mol O2
1 mol CO2
44.0 g CO2
less than 54.1 grams and O2 will be limiting
A 2.634 g mineral sample that contains impure CuCl2·2H2O was heated until all the water was driven off. After being
heated, the impure mineral’s mass was 2.125 g. What is the mass percent of CuCl2·2H2O in the original mineral sample.
a)
First we need to calculate how much CuCl2·2H2O is in the mineral sample by knowing how much water was driven off
upon heating
b) 0.509 g H2O
c)
5.
.
1 mol CuCl2 2H2O
2 mol H2O
2.41 g CuCl2 2H2 O
2. 34 g of impure mineral
x 100
.
170.5 g CuCl2 2H2O
.
1 mol CuCl2 2H2O
1 mol H2O
18.0 g H2O
.
2.41 g CuCl2 2H2O
91.5% CuCl2·2H2O in the impure mineral
Nicotine is a poisonous compound found in tobacco leaves with a chemical composition of: 74.0% carbon, 8.65%
hydrogen and 17.35% nitrogen. What’s the empirical and molecular formula given that the molecular mass is 1 2 g/mol?
For carbon
For hydrogen
For nitrogen
This tell us the ratio is: C6.161H8.582N1.239
dividing each number by 1.239 reveals the empirical formula: C5H7N
Seeing as the empirical mass (81) goes into the molecular mass (162) exactly twice, the molecular formula is: C10H14N2
Review
1.
State the orbital label (ex. 2s or 5f) that would be used to define an electron found within: n = 4 , l = 2 and ml = -1
th
4d (the “n” tells us the 4 quantum level, the l tells us it is a “d” subshell, the ml indicates the orbital orientation (note:
there are five “d” orientations)).
2.
Explain how it is possible to have octahedral electron-pair geometry, yet a planar molecular geometry. In addition, state
the bond angles within this planar molecule and explain what term is used to describe the electrons above and below
this plane.
Octahedral electron-pair geometry occurs when atomic bonding radiates in 6 different
bonding pair directions. If the top and bottom atoms are replaced with lone pairs, the
o
resulting molecular geometry is square planar which have 90 angles between the atoms.
3.
What molecular attraction explains why ethanol easily dissolves in water (draw a diagram to facilitate the explanation).
Furthermore, explain why ethane is less likely to dissolve in water.
Hydrogen bonding (aka dipole attraction) causes ethanol to dissolve in water (note the
red dotted lines between the electronegative oxygen atom of one molecule and the
electropositive end of another molecule. Both ethanol and water have polar regions
which provide a mechanism for attraction. Ethane, a nonpolar molecule, will not dissolve
in polar water.
4.
Draw the dash/dot diagram for O2SCl2. Determine the formal charges of each atom and explain why the overall molecule
does not have a charge.
formal charge on “S”
6 - (0 + ½ (8))
+2
formal charge on “O”
6 - (6 + ½ (2))
-1
formal charge on “Cl”
7 - (6 + ½ (2))
0
overall the molecule is neutral because the +2 from sulfur is countered by two of -1 oxygen
charges, whereas the chlorine does not provide a formal charge.
5.
Properly label an MO diagram for CF and explain what the BO indicates. Furthermore, explain the significance of the
lines on the left of the diagram not being the same height as the lines on the right.
C
CF
F
* 2p
2p2
2p2
 2p
 2p
bond order of
2.5
energy
2s2
* 2s
2s2
 2s
According to the diagram, the carbon
electrons contain more energy compared
to the fluorine electrons
* 1s
1s2
1s2
 1s