9/28/2013
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Today
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◦ Questions about Exam 1?
◦ Review:
Next Meeting
◦ Exam 1
◦ Please bring a GREEN SCANTRON
 Practice problems together
 See CANVAS for exam topics & review
materials
Graded Concept Check:
Gram to Mole Conversions: Using Molar Mass
How many moles of Chlorine ATOMS are present in 220
grams of Calcium Chloride (CaCl2)?
Hint: First calculate the # of moles of CaCl2 the 220 gram sample.
A. ½ mole of Cl atoms
Ca = 40.08 amu
Cl = 35.45 amu
B. 1 mole of Cl atoms
C. 2 moles of Cl atoms
D. 4 moles of Cl atoms
E. Cannot determine from information provided
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9/28/2013
Counting Significant Figures
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0.00309 grams
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1.0 x 10-3 L
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0.0890 m
Density: A bridge between Mass & Volume
It was said that Thor’s hammer was forged from a dying star (with
a density = 3.7 x 1014 g/mL). If the hammer had a volume of 4.41
Liters (L), calculate the total MASS of Thor’s hammer.
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9/28/2013
Significant Figures in Addition and Subtraction

101.3 mL + 1.98 mL =
iClicker Question:
Converting between units of VOLUME
How many m3 are in 13.9 cm3?
Given: centi = 1 hundredth = 10-2
A. 13900000 m3
B. 1390 3
C. 0.139 m 3
D. 0.00139 m3
E. 0.0000139 m3
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9/28/2013
Atomic Theory
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Describe the relative size, mass, & charge of each
component of an atom.
What makes one element unique from another?
What is true about a neutral atom?
◦ What about an anion? What about a cation?

What is different from one isotope to another?
Naturally occurring Bromine consists of 2 stable isotopes:
Br-79, Br-81. Based on the average atomic mass of
Bromine, which isotope is most abundant?
A. Bromine-79
B. Bromine-80
C. Bromine-81
D. They are all equal in abundance
E. Not enough information has been provided.
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9/28/2013
iClicker PARTICIPATION Question:
Determining Isotopic Abundance
Naturally occurring Germanium consists of four stable
isotopes: Ge-70, Ge-72, Ge-73, Ge-74. Based on the
average atomic mass of Germanium, which isotope is
most abundant?
A. Germanium-70
B. Germanium-72
C. Germanium-73
D. Germanium-74
E. Not enough information has been provided.
The heart of CHEMISTRY
The MOLE
Molar Mass:
g/mol
Mass (g)
NA:
6.022 x 1023
particles/mol
# of Particles
Density:
g/mL
• atoms
• molecules
• ions
• formula units
Volume (mL)
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9/28/2013
Proceeding clockwise from
the top samples containing
one mole each: copper,
aluminum, iron, sulfur,
iodine, and (in the center)
mercury.
Conversion with Moles

How molecules are in 7.5 grams of nitrogen gas? How
many nitrogen atoms are present?
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9/28/2013
Conversion with Moles
What is the volume of 3.01 x 1023 atoms of iron (Fe)?
Hint: the density of iron is 7.87 g/cm3.

iClicker Question:
Converting between units of VOLUME
What is the name of the substance below?
Fe2(SO3)3
A. Iron Sulfate
B. Diiron trisulfate
C. Iron (II) Sulfite
D. Iron (III) Sulfite
E. Iron Sulfite
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9/28/2013
Nomenclature: Names to Formulas OR Formulas to Names
Classify each as an ionic or covalent compound

N2O5
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Sr(ClO4)2
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Ammonium Phosphate
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Cobalt (II) Carbonate
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Phosphorus Pentaiodide
What is WRONG with each name or formula below?
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BaNO3
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KSO4
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Ruthenium (II) Sulfate = Ru2(SO4)4
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Iron Bromide = FeBr3
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Sodium Chlorine Tetraoxide = NaClO4
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