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CHEM 10050
Fall 1996
Final Exam
Name___________________
Soc. Sec.#_______________
P1V1 P2V2
Formula’s: PV=nRT, T
= T , Ptotal= Pa + Pb + Pc..., Kw = [H+][OH-] = 1.0 x 101
2
heat (J)
14, pH = -log [H+], specific heat =
g x ∆T(°C) , ∆G = ∆H – T∆S
Conversion units and constants: 101.3 kPa = 1 atm, 29.9 in. Hg = 1 atm,
760 torr = 1 atm, 22.4 L = 1 mole at STP, 6.022 x 10 23 units = 1 mole, 760 mm Hg =
760 torr, 1 mile = 1.61 km, 1 in. = 2.54 cm, 1 kg = 2.205 lb, 1 lb = 454 g, 1 L = 1.057 qt.,
1 qt. = 946 mL, 4.184 J = 1 cal, 32 oz. = 1 qt., 4 qt. = 1 gallon
R = 0.0821 L-atm/mol-K
Multiple Choice (4 pts. each)
____
1. What is the molarity of a solution prepared by dissolving 1.25 mol of AgNO 3
in enough water to make 625 mL of solution?
a) 2.00 M
____
____
c) 9.13 mol
d) 10.0 mol HCI
b) 2.5 g
c) 6.3 g
d) 10 g
+
d) NH 4
5. If the concentration of OH– is 4.0 x 10–2 M, the concentration of H3O+ is?
b) 4.0 x 1012 M
c) 4.0 x 10–2 M
d) 1.0 x 10–14 M
6. The correct formula for copper (II) nitrate is:
a) CuNO3
____
b) 0.250 mol
4. In the reaction shown below, the conjugate acid of NH3 is:
–
+
H2CO3 + NH3  HCO 3 + NH 4
–
a) H2CO3
b) HCO 3
c) H3O+
a) 2.5 x 10-13 M
____
d) 0.340 M
3. How many grams of NaOH are needed to make 250 mL of a 2.5% (w/v)
solution?
a) 1.3 g
____
c) 0.500 M
2. How many moles of HCI are present in 50.0 mL of a 0.200 M solution?
a) 0.0100 mol
____
b) 0.00200 M
b) Cu2NO3
c) Cu(NO3)2
d) Cu2(NO3)2
7. Which of the following measurements has three significant figures?
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a) 4.00
____
b) boiling point
c) osmotic pressure
d) density
b) Ca
c) S
d) Br
b) electrolytes
c) non-electrolytes
d) allotropes
b) NH3
c) CH4
d) H2
c) 7
d) 9
decrease the heat of reaction (∆H)
decrease the energy of activation (Ea).
decrease the free energy (∆G).
decrease the entropy (∆S).
16. In an experiment where a pair of electrodes is immersed into an aqueous
solution of sodium chloride, the chloride ions will migrate towards the:
a) cathode
____
d) none of these
15. The function of a catalyst in a reaction system is to:
a)
b)
c)
d)
____
c) 343 K
14. A solution of which pH is most acidic:
a) 3 b) 5
____
b) 70 K
13. Which of the following is a Lewis base:
a) CO2
____
d) 18.8 g
12. Compounds that conduct electricity when dissolved in water are called:
a) covalent
____
c) 31.6 g
11. Which of the following elements is a halogen?
a) Na
____
b) 48.0 g
10. Which of the following is not a colligative property:
a) melting point
____
d) all of these
9. 158 °F is equivalent to:
a) 125 °C
____
c) 324.0
8. What is the mass of 30.0 mL of a solution with a density of 1.60 g/mL?
a) 0.053 g
____
b) 0.002
b) anode
c) commode
d) electrolyte
17. Which subatomic particle has a relative mass of approximately one mass
unit and a charge of zero (0)?
a) neutron
b) proton
c) electron
d) alpha particle
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____
18. The reaction between a proton donor and a proton acceptor is called:
a) neutralization
c) decomposition
____
19. Which of the following is an electrolyte?
a) H2O
____
b) electrolysis
d) single displacement
b) sugar (C6H12O6)
a)
b)
c)
d)
c) 69.5 g
d) 0.0144 g
63
b) 29 neutrons
c) 63 electrons
d) 34 neutrons
22. What is the pH of a solution in which [H3O+] = 3.2 x 10–6 M?
a) 3.1 x 10–9
____
b) 0.006 g
21. The copper isotope 29 Cu contains:
a) 63 protons
____
d) CH4
20. The mass of 1.45 moles of tin is:
a) 172 g
____
c) NaCl
b) 8.5
c) 7.0
d) 5.5
23. When a non-volatile solute is dissolved into a solvent the:When a nonvolatile solute is dissolved into a solvent the:
vapor pressure decreases, melting point decreases, and boiling point decreases.
vapor pressure increases, melting point decreases, and boiling point increases.
vapor pressure decreases, melting point increases, and boiling point increases.
vapor pressure decreases, melting point decreases, and boiling point increases.
____
24. During osmosis, ______ passes through a semi-permeable membrane
from regions of _______ concentration to regions of ______ concentration.
a. solute, low, high
c. solvent, low, high
____
b. solute, high, low
c. solvent, high, low
25. The prefix “centi-” used in the metric system indicates:
a. 10–1
b. 10–2
c. 10–3
d. 10–6
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Solve the following problems showing all work. Answer essay questions using
complete sentences. Remember to use proper units, significant figures and
rounding.
1) Describe the Arrhenius, Brønsted-Lowery, and Lewis Acid-Base theories.
representative examples of acids and bases for each description. (20 pts.)
Use
2) Use the periodic table of elements to complete the following (20 pts.):
a) Identify the following classes of elements by group number and state an example
of each using a written name and elemental symbol: halogens, transition metals,
noble gases, alkali metals.
b) Compare the physical properties of metals with those of non-metals.
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c) Identify the seven diatomic elements giving the elemental symbols and written
names.
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3) Draw Lewis structures and predict geometry’s for the following. (20 pts.):
a) SO3
+
b) NH 4
c) OF2
d) C2H2
4) Make the following conversions using the correct number of significant figures
(20 pts).
a) 3.00 years to seconds
b) 36.0 gallons to milliliters
c) 28 pounds to milligrams
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d) 2.00 miles to micrometers
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5) a) Calculate the number of milliliters of carbon dioxide gas produced at 710 torr and
28.0°C when 22.35 mL of 0.2458 M HCl is reacted with sodium carbonate according
to the following equation (20 pts.):
2HCl + Na2CO3  NaCl + CO2 + H2O
b) What was the percentage yield for this reaction if 26.5 ml of CO 2 was actually
collected?
c) Is this a redox reaction? If so, identify the oxidizing and reducing agents.