Download Final Exam Review Sheet

Chem 42 Final Review Sheet
Mr. J. Fassler
Spring 2017
These problems are given to help you review concepts you may have forgotten.
Old tests, quizzes and review sheets are also important in studying.
Chapter 4 (Atoms and Ions)
1. Fill in the blanks for each ion.
ion
protons
neutrons
–
electrons
19
F
_______
_______
_______
64
Cu2+
_______
_______
_______
Electron Configurations
2. Write ground state electron configurations for the following elements and ions:
C ________________________________
F ________________________________
Al ________________________________ Ca2+ ______________________________
Mn _______________________________ Br– ________________________________
Chapter 5 (Nomenclature)
3. Name the following compounds.
CaO ______________________________ Mg3(PO4)2 ________________________________
PCl5
_____________________________ Cu2O ____________________________________
PbO2 ______________________________ NaHCO3 ________________________________
CrO3 _______________________________ Fe3(PO4)2 ________________________________
4. Write formulas from the following names, being sure that the charge is zero for each
formula.
carbon tetrachloride ________________
lead (II) chloride
________________
lithium carbonate
________________
copper (I) iodide
________________
ammonia
________________
magnesium sulfide
________________
ammonium chloride ________________
silver nitrate
________________
gold(I) cyanide
________________
hydrogen peroxide
________________
iron(III) sulfate
________________
calcium hydroxide
________________
magnesium nitrate
________________
phosphorus trichloride ________________
Writing chemical equations (Chapter 7)
5. Write and balance the complete molecular, complete ionic and net ionic equations for
each of the following reactions. Refer to the solubility rules as needed.
a. Aqueous sodium sulfate is mixed with aqueous calcium chloride.
b. Aqueous ammonium phosphate is mixed with aqueous aluminum nitrate.
c. Aqueous copper(II) sulfate is mixed with sodium sulfide.
d. Aqueous hydrochloric acid reacts with aqueous calcium hydroxide.
Periodic Trends (Chapters 10 and 11)
6. What is electronegativity?
7. Which element is most electronegative? _______ Least electronegative? _______
Lewis Structures/VSEPR (Chapter 6)
8. Draw Lewis structures for the following molecules and ions, including any formal
charges and resonance structures. Also identify the shape of the molecule using VSEPR.
PH3
CO32–
shape
O2
shape
SO2
shape
SO3
shape
C2H4
shape
C2H2
shape
H2N2
shape
shape
Oxidation Numbers/Redox Reactions (Chapter 10)
10. Assign oxidation numbers and decide what substances are being reduced and oxidized
in the reactions below.
a. 2 HgO (s) à O2 (g) + 2 Hg (l)
b. 2 Al (s) + 3 FeO (s) à Al2O3 (s) + 3 Fe (l)
Bonding & Intermolecular Forces (Chapter 7)
11. Explain the difference between an ionic bond and a covalent bond.
12. Explain the difference between bonds and intermolecular forces.
13. Use intermolecular forces to explain why H2O is a liquid, but H2S is a gas.
14. Use intermolecular forces to explain why Cl2 is a gas, Br2 is a liquid, and I2 is a solid.
Gases (Chapter 11)
15. For a friend's birthday, you buy a helium balloon with volume 4.20 L at 20. °C. In
order to get a better return on your investment, you decide to leave the balloon in a hot car
until the temperature increases to 40. °C. Assuming pressure is constant, find the new
volume of the balloon.
16. In photosynthesis, the reaction 6 CO2 (g) + 6 H2O (l) ⎯→ C6H12O6 + 6 O2 (g) occurs.
How many liters of oxygen at 20. °C and 0.90 atm will be produced if 6.2 grams of water
are consumed?
Solutions (Chapter 12)
17. What is the molarity of a solution of 3.2 moles of sugar in 0.276 L?
18. If you dissolve 40.0 g CuSO4 to a volume of 1.2 L, what is the concentration in
moles/L?
19. How many liters of 0.335 M Na2SO4 are needed to precipitate all the calcium ions in
6.24 L of 0.557 M CaCl2?
CaCl2 (aq) + Na2SO4 (aq) à CaSO4 (s) + 2 NaCl (aq)
Energy in Reactions (Chapter 13)
20. a. Draw an energy diagram showing the change in energy for the endothermic reaction
shown below.
H
H
O
C
H
H
H
C
H
C
O
C
H
H
H
H
H
H
b. Label the transition state, activation energy, reactants and products in your graph above.
Equilibrium (Chapter 14)
21. For the reaction below, predict the effect on the equilibrium for each of the changes
indicated.
heat + 2 SO3 (g)
Change
2 SO2 (g) + O2 (g)
Equilibrium shifts (left/right)
Temperature is increased
SO3 is removed
O2 is removed
SO2 is added
22. Use Le Chatelier’s principle to predict the effects on the equilibrium below in the
following situations.
C (s) + 2 H2 (g)
Change
CH4 (g) + heat
Equilibrium shifts (left/right)
Temperature is increased
H2 is added
CH4 is removed
23. For the equilibrium below, predict how the concentrations of the different species
would change under the given circumstances:
O
O
H2O
H3O
OH
propanoic acid
a. [H3O+] is increased.
Eqilibrium shifts
[propanoic acid]
[propanoate]
water
propanoate
left
increases
increases
right
decreases
decreases
b. [propanoic acid] is increased.
Equilibrium shifts left
[propanoate]
increases
+
[H3O ]
increases
right
decreases
decreases
O
hydronium
Acids and Bases (Chapter 15)
24. Write the Brønsted-Lowry definition of an acid and a base.
25. Identify the acid and its conjugate base in each of these reactions:
HCl + H2O ⎯→ Cl– + H3O+
H3O+ + OH– ⎯→ H2O + H2O
HS– + OH– ⎯→ S2– + H2O
H2PO4– + HI ⎯→ H3PO4 + I–
26. Identify the acid and base in each forward reaction.
a. CH3OH (aq) + HI (aq)
CH3OH2+ (aq) + I– (aq)
b. HSO4– (aq) + HCO3– (aq)
H2CO3 (aq) + SO42– (aq)
c. HSO4– (aq) + HCO3– (aq)
CO32– (aq) + H2SO4 (aq)
d. 2 CH3COO–(aq) + H3PO4 (aq)
2 CH3COOH (aq) + HPO4–2
27. (2 pts) Fill in the blanks (remember, conjugates differ by the presence of H+).
Acid
Conjugate base
CH3OH2+
H2CO3
SO42–
HSO4–
28. (8 pts) Calculate the missing quantities:
Solution
[H3O+]
Coke®
beer
pH
[OH–]
pOH
acidic or
basic?
2.5
3.16 x 10–7
bleach
2.00 x 10–2
seawater
5.78
pure water
Strong and weak acids/bases
29. Write definitions for weak acids/bases and strong acids/bases.
30. Write balanced equations that show the dissolution of:
a. HCl in water
b. Ca(OH)2 in water
31. Calculate the pH, [OH–] and pOH of a solution where [HCl] = 3.2 x 10–4 M.
32. Calculate the concentration of Ca(OH)2 in a solution with pH 13.951
neutral