Chemistry Lab Methods Practice FINAL
Name ______________________________ Period:_____
Do your best to answer all of these questions. Use your notes, book, quizzes, old homework, and classmates as resources. The
answer key will be posted on my Lab Methods website in the “Useful Files” folder by the end of the day Friday, 1/17.
Section 1: Lab Safety and Scientific Method
1. Write the volume measurement AND units for each of the following pictures:
a.
b.
c.
2. Convert the following measurements to the indicated units:
a. 532 mL to liters (L):
b. 3.6 L to milliliters (mL):
c. 97.4 g to kilograms (kg):
d. 0.5492 kg to grams (g):
Section 2: Atoms and the Periodic Table
3. Noble gases are naturally:
a. Very reactive
c. Diatomic
b. Very unreactive (stable)
d. Able to make ions with multiple charges
4. What element will have the same number of valence electrons as magnesium?
a. Nitrogen
c. Sodium
b. c. Chlorine
d. d. Calcium
5. How many protons does Lead-207 have?
a. 82
c. 125
b. 207
d. -125
6. How many neutrons does Lead-207 have?
a. 82
c. 125
b. 207
d. -125
7. What is the mass number of Lead-207?
a. 82
c. 125
b. 207
d. -125
8. Which element has 9 protons?
a. Beryllium
c. Potassium
b. Fluorine
d. Neon
9. Where do you find nonmetals on the periodic table?
a. In the middle valley by transition metals
c. Along the zig-zag line
b. In the upper right corner
d. On the left of the table
10. In the periodic table, what are the columns (vertical) called?
a. Groups
c. Rows
b. Periods
d. Noble gases
Section 3: Atomic Models
11. How many electrons fit in the first (lowest) energy level?
a. 8
c. 6
b. 2
d. 1
12. The image to the right shows the model of a neutral atom of this element
a. Hydrogen
b. Neon
c. Oxygen
d. Nitrogen
e. Fluorine
13. Electrons travel between orbits of atoms and can be found in many places in-between each orbit’s energy
level at any given time.
a. True
b. False
14. Sodium has ____ electron(s) in the valence shell.
a. 1
c. 6
b. 2
d. 7
15. The image to the right is a representation of which of the following neutral atoms?
a. Hydrogen
d. Neon
b. Nitrogen
e. Helium
c. Oxygen
16. The most common isotope of Cobalt is:
a. Cobalt-27
c. Cobalt-58
b. Cobalt-59
d. Cobalt-58.9
17. The most common isotope of Titanium, has __________ neutrons:
a. 22 neutrons
c. 26 neutrons
b. 24 neutrons
d. 48 neutrons
Section 4: Radioactivity
18. An alpha particle is actually a(n) ____________________ .
a. Hydrogen atom
b. Positive hydrogen ion
c. Helium atom nucleus
d. Collection of only 2 neutrons and nothing else
19. When an unstable isotope undergoes beta decay the nucleus of the atom that is decaying _________ .
a. Always becomes even more unstable
c. Gains 1 more proton
b. Gains 1 more neutron
d. Gains 1 amu of mass
20. Gamma decay emits __________
a. A proton
c. Energy
b. An electron
d. A neutron
21. Rhenium 187 undergoes beta decay. What isotope of which element does it become?
a. Hydrogen-2
d. Tungsten -187
b. Carbon-14
e. Osmium -187
c. Osmiium-186
22. Which type of radiation involves the most massive (biggest, heaviest) particles?
a. Alpha
c. Gamma
b. Beta
d. Visible light
23. What happens to the attractive power of the strong nuclear force as the distance between 2 nucleons
increases.
a. It gets considerably weaker
b. It isn’t affected much by increasing distances between interacting particles
c. It behaves similarly to the electrostatic force and its strength diminishes over distance but still has a
significant influence over a wide range of distances.
24. A Uranium-238 atom will become ___________ after emitting an alpha particle.
a. It will stay uranium -239 even after
c. It will turn into uranium-234
emitting an alpha particle
d. It will turn into iron atoms
b. It will turn into thorium-234
25. The half life of radium 224 is 3.6 days while the half life of radium 226 is 1601 years. Suppose you had a 1
gram sample of each isotope. Which isotope of radium will emit more radiation in one day?
a. the radium 224
b. the radium 226
c. they will have equal radioactivity behavior since they are both samples of the same element – radium
26. Jenny found an arrow shaft in an old native American burial site and had it tested for carbon 14 content. The
report came back that the artifact had about ¼ of the radioactive material found in a modern living tree. What
would the age of the arrow be based on carbon 14 dating methods. (The accepted value for the ½ life of
carbon-14 is 5730 years)
a. 5730 years
d. 22920 years
b. 11460 years
e. 1432.5 years
c. 17190 years
27. When people do carbon 14 dating, what assumption are they making as they do their work?
a. That carbon-14 is the same as carbon-13
b. That carbon 14 is radioactive
c. That the percentage of carbon-14 in the environment was the same when the organism being tested
was alive as there is now in modern times.
28. As the size of the nucleus gets larger, the strong nuclear force between particles on opposite sides of the
nucleus together gets:
a. Stronger.
b. Weaker.
c. Doubles.
d. Stays the same.
29. As you move down the columns / families in the periodic table, the size of the atoms of each element get:
a. Smaller
b. Larger
c. Stay the same
d. Should get larger, but don’t
Section 5: Bonding and Nomenclature
30. What is the charge of the anion in Na2O?
a. +1
c. -1
b. +2
d. -2
31. Which electrons are involved in bonding to make compounds?
a. Electrons closest to the nucleus
c. Electrons in the second orbital
b. Valence electrons
d. Electrons in the first orbital
37. What is the name of the anion in K2SO4?
a. Sulfide
c. Sulfate
b. Sulfite
d. Potassium ion
41. How many electrons do most chemically stable atoms have in their outside level?
a. 2
c. 18
b. 8
d. 6
+
42. In the symbol Na , the + tells us:
a. The charge on a sodium ion
c. The number of sodium atoms present
b. The number of electrons the sodium atom
d. Both A and B
lost
43. What types of elements usually form ionic compounds?
a. Metals and nonmetals
c. Metals and metals
b. Nonmetals and nonmetals
d. Transition and inner transition metals
44. What types of elements usually form covalent compounds?
a. Metals and nonmetals
c. Metals and metals
b. Nonmetals and nonmetals
d. Transition and inner transition metals
45. What is the formula for the ionic compound made of calcium and chlorine?
a. CaCl
b. Ca(II)Cl
c. CaCl2
d. Ca2Cl
46. How many electrons are in a single covalent bond?
a. 1
c. 3
b. 2
d. 4
47. In MgBr2, how many electrons did magnesium lose or gain?
a. Lost 1
c. Gained 1
b. Lost 2
d. Gained 2
48. Do molecules have ionic or covalent bonds?
a. Ionic
b. Covalent
c. Both
49. Which of these is a polyatomic ion?
a. S2c. Na+
b. SO42d. NH4Cl
50. What is the name of Fe2O3?
a. Iron (II) oxide
c. Iron (III) oxide
b. Iron hydroxide
d. Diiron trioxide
51. What is the name of AlCl3?
a. Aluminum trichloride
c. Aluminum chloride
b. Aluminum (III) chloride
d. Aluminum chlorate
52. What holds ionic compounds together?
a. Sharing of electrons
c. Gravitational attraction
b. Electrostatic attraction between positive
d. Nuclear strong force
and negative charges
53. What is the total number of protons and neutrons in an O2 molecule?
a. 24
c. 16
b. 32
d. 8
54. What happens if you take electrons away from an atom?
a. The atom will become a different element
c. The atom will become a positive ion
b. The atom will be an isotope
d. The atom will become a negative ion
Section 6: Chemical Reactions
54. Which of these solutions conducts electricity BEST?
a. A solution of covalently bonded sugar molecules (C12H22O11)
b. An ionic solution of NaCl
c. Deionized water
55. What does the 3 mean in 2Fe2(SO4)3?
a. Three oxygens total
c. Three sulfates for every two irons
b. Three sulfates total
d. Three molecules
56. Which of the following are not naturally occurring in pairs (diatomic)?
a. N
c. I
b. H
d. K
57. Why do we balance chemical equations?
a. Because we have to end up with as many atoms as we started with
b. Because all chemical reactions create hydrogen gas
c. Because we want to make more of the product
d. Because each compound needs to have a neutral charge
58. If this equation were balanced, what coefficient would go in front of lithium bromide?
____ LiCl + ____ Br2  ____ LiBr + ____ Cl2
a. 1
c. 3
b. 2
d. 4
59. If this equation were balanced, how many carbon dioxide molecules would be formed?
____ C4H12+ ____ O2  ____ CO2 + ____ H2O
a. 6
c. 1
b. 7
d. 4
60. When the following equation is balanced, what are the coefficients (in order from left to right)?
___ CaCO3  ___ CaO + ___ CO2
a. 2, 3, 2
c. 3, 2, 1
b. 1, 2, 2
d. None of the above
61. If this equation were balanced, what coefficient would go in front of hydrogen bromide?
___CaBr2 + ___HF  ___CaF2 + ___HBr
a. 1
c. 3
b. 2
d. 4
Section 6: Labs & Demos
62. We used the Hoffman Apparatus (pictured) to decompose water into two elements
hydrogen and oxygen. What did we need to do to get the reaction started?
a. Evaporate the water by adding thermal energy
b. Add energy by running an electrical current through the system
c. Put the water into a clear, glass cylinder
d. Add a different chemical compound to the water
We collected different gases during different labs and demonstrations.
Match the gas we collected to the method used to test for the gas:
63. Oxygen gas (O2)
a. A “pop” noise when held near a flame
b. A “flare up” when held near a flame
64. Hydrogen gas (H2)
c. Extinguished the flame when “poured”
65. Carbon dioxide gas (CO2)
on it.
Use the following pictures to answer questions 66 & 67:
a.
b.
c.
66. Rutherford fired positive particles at gold foil. Which picture represents the commonly accepted atomic
model before he did his experiments?
67. In Rutherford’s experiment, most of the particles went through the foil, but some “bounced back”. Which
picture represents the atomic model he developed after he did his experiments
68. Other labs to review:
a. Ruler Lab
b. Properties of Ionic vs. Covalent Compounds
c. Language of Change
d. Conservation of Mass
e. Bubbling Egg
f. “The black snake” – decomposition of sugar
g. Single Replacement Reactions: metals in solutions
h. KI + Pb(NO3)2 Precipitate Lab
i. Get a Half Life
Consider: the techniques we used, the conclusions we reached and the evidence we had
for each lab!!
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