Chemistry 110 – 02
Fall 2016
Seventh Homework
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Finish studying Hill and McCreary Chapter 5 sections 1, 3, 4, and 5.
Begin studying Hill and McCreary Chapter 6 sections 1 - 5.
On Thursday we will meet in 15-302, 7:30 – 9:20.
The sixth quiz will include questions from the topics below. To be prepared for the quiz, you should
be able to answer these questions using only the periodic table you received in class and the
information given. Any quiz may include questions about lab safety and procedures.
Due 8:30 am Wednesday, November 2. 10 Points.
Late homework is not accepted after 8:30 am Thursday, November 3.
1. Write the formula for each of these compounds.
a. sodium nitrate
b. potassium carbonate
d. magnesium phosphate
e. calcium cyanide
g. aluminum bromide
h. ammonia
c. ammonium sulfate
f. lithium acetate
i. calcium chlorate
2. Give the name of each of these.
a. K2SO4
d. BaCl2
c. LiOH
f. NaCH3CO2
b. Ca(HCO3)2
e. NH4Cl
3. For each of these pairs of molecules, indicate whether they are isomers or are the same
compound. (I strongly recommend you borrow the model kit from the Building 15 office or the
Tutoring Center and make these molecules to check your answer)
Cl
a.
c.
H
Cl
C
C
H
H
H
H
C
F
Cl
H
H
H
F
H
C
C
H
Cl
F
H
b.
H
C
H
H
C
H
C
F
F
C
F
F
C
C
H
C
F
4. For each molecule, use VSEPR to determine the shape of the molecule. For each molecule, draw
the shape of the molecule, give the name of the shape of the molecule. Then indicate whether it is
a polar molecule or a nonpolar molecule.
a. CO2
b. H2CO
c. CH3F
d. H2O
e. NH3
5. Draw an electron dot structure for each of the following molecules. Include all lone pairs.
Then indicate whether it is a polar molecule or a nonpolar molecule.
a. C3H6O2
b. CS2
c. C3H9N
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6. For each molecule, draw the electron dot structure. Then indicate whether it is a polar molecule
or a nonpolar molecule.
a. C3H8O
b. CH3CHO
c. C2H2
7.
For each compound, indicate whether it is a molecular compound or an ionic compound.
a. NaCl
b. H2O
c. CaF2
d. K2SO4
e. CO2
f. NH4Br
8.
Sketch what a piece of NaCl looks like at the nanoscale.
9.
Identify the reactant(s) and the product(s) in each of these chemical equations.
a. H2S + O2  H2SO4
b. C6H12O6  CH3CH2OH + CO2
10. Write the chemical equation for each of these reactions. You do not need to balance them.
a. Magnesium hydroxide and hydrochloric acid (HCl) react to produce magnesium chloride
and water.
b. Propane (C3H8) and oxygen react to produce carbon dioxide and water.
c. Nitrogen and hydrogen react to produce ammonia.
11. The equations in this question are modified from Microbial Metabolic Diversity – The Tip of
the Iceberg, by Dr. Ruth Ann Mikels, which states, “Each of the following equations represents
a metabolic activity carried out by various species of bacteria.”
Balance each equation.
a.
N2 + H2 → NH3
(nitrogen fixation)
b.
CO2 + H2O → C6H12O6 + O2
(photosynthesis)
c..
H2S + O2 → H2SO4
d.
C6H12O6 → CH3CH2OH + CO2
(alcoholic fermentation)
e.
CO2 + H2S → C6H12O6 + S + H2O
(anoxygenic photosynthesis)
f.
C6H12O6 → CH3CHOHCOOH
g.
NH4Cl + O2 → HNO2 + HCl + H2O
12. Alcoholic fermentation is C6H12O6 → CH3CH2OH + CO2
a. Write the balanced equation (see your answer to the previous question).
Interpret the balanced equation for alcoholic fermentation in terms of
b. molecules of each reactant and molecues of each product. (Nanoscale interpretation.)
c. moles of each reactant and moles of each product. (Molar interpretation.)
d. grams of each reactant and grams of each product.
13. Anoxygenic photosynthesis is CO2 + H2S → C6H12O6 + S + H2O
a. Write the balanced equation (see above).
Interpret the balanced equation for anoxygenic photosynthesis in terms of
b. molecules of each reactant and molecules of each product. (Nanoscale interpretation.)
c. moles of each reactant and moles of each product. (Molar interpretation.)
d. grams of each reactant and grams of each product.
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14. You have a 0.677 M KNO3 solution.
a. What is the solute?
b. What is the solvent?
c. How many moles of KNO3 are in 55.0 mL of the solution?
15. You have a 0.148 M NH3 solution.
a. “mL” is the symbol for “milliliter”. “M” is the symbol for __________________.
b. How many mL of the solution contains 0.0733 moles of NH3?
16. You have a 0.385 M sodium chloride solution.
a. What volume of the solution in mL contains 0.123 moles of sodium chloride?
b. How many moles of sodium chloride is in 135 mL of the solution?
17. Some KBr dissolves in water. Sketch how the ions and the water molecules are arranged in
this solution. (I recommend you run the Dissolving Salt in Water simulation.) Show only one
KBr, but show many H2O.
18. Which of these soluble compounds are electrolytes?
a. NaCl
b. CH3OH
c. KOH
d. Na2SO4
19. In the early 20th century, Arrhenius won a Nobel Prize in Chemistry for discovering that
electrolyte solutions contain ____________________.
20. Which one of these has the strongest London dispersion attractions in the pure element?
He, Ne, Ar, or Kr
21. For each of these compounds, indicate whether London dispersion attractions, dipole-dipole
attractions, and/or hydrogen bonding are present between the molecules of the pure compound.
a. ethane (CH3CH3)
b. chloromethane (CH3Cl)
c. formaldehyde (H2CO)
d. methanol (CH3OH)
e. octanol (CH3CH2CH2CH2CH2CH2CH2CH2OH)
22. Predict which compound in each pair will have the stronger intermolecular attractions.
a. ethane (CH3CH3) or octane (CH3CH2CH2CH2CH2CH2CH2CH3)
O
CH3 ) or propanol (CH CH CH OH)
b. acetone (H3C C
3
2
2
c. methane (CH4) or dichloromethane (CH2Cl2)
d. dichloromethane (CH2Cl2) or propane (CH3CH2CH3)
23. Predict which compound in each pair has the higher heat of vaporization.
a. ethane (CH3CH3) or octane (CH3CH2CH2CH2CH2CH2CH2CH3)
O
CH3 ) or propanol (CH CH CH OH)
b. acetone (H3C C
3
2
2
c. methane (CH4) or dichloromethane (CH2Cl2)
d. dichloromethane (CH2Cl2) or propane (CH3CH2CH3)
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24. Run the Intermolecular Attractions and Melting Point simulation on the class web page.
Explore how the strength of the intermolecular attractions affects the melting temperature. (Set
the Intermolecular Attractions to weak and find the temperature at which the solid melts. Repeat
with the Intermolecular Attractions set to medium and strong.) What is the relationship between
the strength of the intermolecular attractions and the melting temperature?
inspired by
- "Like Attracts Like" - Emmett Williams -
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