Chem Sol 2007
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____ 1.
What is the volume of the liquid in the graduated cylinder?
a. 13.00 mL
c. 14.00 mL
13.50
mL
b.
d. 14.50 mL
____ 2. Atoms of the noble gases are generally inert because —
a. they are too large to react
b. they are not charged
c. they are neutral atoms
d. their outer electron levels are filled
____ 3.
What is the mass of a mole of Ca(OH)2?
a. 57 grams
c. 74 grams
b. 58 grams
d. 114 grams
____ 4. Which of these represents a synthesis reaction?
a.
c.
b.
d.
____ 5. Sulfur is represented by the following Lewis dot structure:
Which of the elements has the same Lewis structure?
a. Chlorine
b. Magnesium
c. Oxygen
d. Phosphorus
____ 6. A mixture of gases with a pressure of 800.0 mm Hg contains 60% nitrogen
and 40% oxygen by volume. What is the partial pressure of oxygen in this
mixture?
a. 140.0 mm Hg
b. 320.0 mm Hg
c. 373.0 mm Hg
d. 480.0 mm Hg
____ 7.
The equation shows the combustion of butane (C4H10) How many moles of
water can be produced by 12.5 moles of C4H10 with excess oxygen?
a. 2.50 mol
b. 62.5 mol
c. 125 mol
d. 202 mol
____ 8. The formula for magnesium chloride is —
a. MnCl
b. MnCl2
c. Mg2Cl3
d. MgCl2
____ 9. What are the numbers of protons, neutrons, and electrons in an isotope of
titanium with a mass number of 50?
a. 22 p, 22 n, 28 e
b. 28 p, 22 n, 22 e
c. 50 p, 22 n, 50 e
d. 22 p, 28 n, 22 e
____ 10.
Water and ammonia have different molar heats of vaporization. The best
interpretation, at the molecular level, is that water molecules —
a. have stronger intermolecular
c. set up stronger repulsive nuclear forces
attractions
b. occupy larger molecular volumes
d. collide more frequently with each
other
____ 11. Which of these statements describes what happens to the molecules of a solid
as the temperature is lowered to absolute zero (-273oC)
a. They begin to take up more space.
c. Their kinetic energy gradually
b. They become farther apart.
increases to a maximum.
d. Their motion gradually decreases and
eventually stops.
____ 12. A sample of iron has a volume of 10.0 mL. The density of iron is 7.87 g/mL.
Which is the correct expression to calculate the mass of the sample using
dimensional analysis?
a.
c.
b.
d.
____ 13.
What mass of nitrogen is required to react with 16 grams of oxygen?
a. 2.8 g
b. 5.6 g
c. 14 g
d. 56 g
____ 14. Hydrogen chloride can be formed from hydrogen and chlorine as shown in the
reaction.
Chlorine and fluorine are located in the same group in the periodic table. If
the reaction were performed with fluorine instead of chlorine, how many
moles H2 of would be required to balance the equation?
a. 1
b. 2
c. 4
d. 8
____ 15. The correct name for Mg3(PO4)2 is —
a. magnesium phosphite
b. trimagnesium phosphate
c. magnesium(III) phosphate
d. magnesium phosphate
____ 16. How many protons are in an atom represented by
a. 88
b. 132
?
c. 220
d. 308
____ 17.
Four students each took three temperature readings of a sample of water.
The actual temperature of the sample was 80.0C. Which student’s
measurements were both accurate and precise?
a. Student 1
b. Student 2
c. Student 3
d. Student 4
____ 18. According to the kinetic-molecular theory of gases, molecules of an ideal
gas —
a. travel in curved lines of motion
b. undergo elastic collisions
c. are separated by small distances
d. have strong forces between them
____ 19. What is the molar mass of beryllium oxide (BeO)?
a. 12 g/mol
b. 13 g/mol
c. 24 g/mol
d. 25 g/mol
____ 20. Catalytic converters made of palladium (Pd) reduce automobile pollution by
catalyzing the reaction between unburned hydrocarbons and oxygen. How
does Pd increase the rate of this reaction?
a. By cooling the reactants
c. By giving the hydrocarbons a negative
charge
b. By splitting the oxygen atoms
d. By decreasing the activation energy
____ 21. A chloride ion has the same number of electrons as a neutral atom of —
a. fluorine
b. sulfur
c. argon
d. bromine
____ 22. Which of these is the proper method for using a thermometer to measure the
temperature of liquid in a beaker?
a. F
b. G
c. H
d. J
____ 23.
Which of the following is most likely the electronegativity value for chlorine?
A 2.3
B 2.7
C 3.0
D 4.2
a. 2.3
b. 2.7
c. 3.0
d. 4.2
____ 24. Which compound has a covalent bond?
a. CaI2
b. KBr
c. NaCl
d. NO
____ 25.
If 5.0 moles of C3H8 react, how many molecules of water are formed?
24
a. 3.0 x 10
24
b. 4.8 x 10
25
c. 1.2 x 10
25
d. 2.4 x 10
____ 26. Which of these best describes sublimation?
a. A solid changing to a liquid phase
b. A solid changing to a gaseous phase
c. A gas filling the space in its container
d. A liquid taking the shape of its
container
____ 27. If the difference in electronegativity between atoms of different non-metals is
small, the atoms of the two non-metals will most likely —
a. form an ionic bond
c. form a covalent bond
b. form a hydrogen bond
d. form a metallic bond
____ 28. The role of a catalyst is to affect —
a. electronegativity
b. heat content
c. activation energy
d. ionization energy
____ 29. Which of these best describes the difference between the formulas for
nitrogen monoxide and nitrogen dioxide?
a. Nitrogen monoxide has one more atom c. Nitrogen monoxide has one fewer
of nitrogen.
b. Nitrogen dioxide has one fewer atom
of oxygen.
atom of oxygen.
d. Nitrogen dioxide has one more atom of
nitrogen.
____ 30. Sulfuric acid (H2SO4)is spilled on a laboratory bench. Which chemical would
be useful for neutralizing the acid?
a. Aluminum chloride (AlCl3)
b. Potassium nitrate (KNO3)
c. Silver iodide (AgI)
d. Sodium bicarbonate (NaHCO3)
____ 31. When compared to sulfur-32, sulfur-34 has more —
a. protons
b. neutrons
c. energy levels
d. bonding configurations
____ 32.
The graph shows five data points collected in an investigation of the
relationship between the concentration of alcohol dissolved in water and its
density. The relationship was expected to be linear. Which of the data points
most likely resulted from an error in procedure?
a. 1
b. 2
c. 4
d. 5
____ 33. What is the chemical name for the compound P3N5?
a. Triphosphorus nitride
b. Phosphorus(III) nitride
c. Triphosphorus pentanitride
d. Pentaphosphorus trinitride
____ 34. In HNO3 the oxidation state of hydrogen is +1 and the oxidation state of
oxygen is -2. Therefore, the oxidation state of nitrogen is —
a. -1
b. +1
c. +4
d. +5
____ 35.
The graph shows the phase diagram of a substance. At which point on the
diagram do the solid, liquid, and gas phases coexist simultaneously?
a. 1
b. 2
c. 3
d. 4
____ 36. The partial pressures of the gases that comprise air are shown in the table.
Partial Pressures
of Gases in Air
If the total atmospheric pressure is 760.00 mm Hg, what is the partial
pressure of CO2?
a. 0.03 mm Hg
b. 0.24 mm Hg
c. 7.36 mm Hg
d. 759.76 mm Hg
____ 37. Which is the safest practice when heating the contents of a test tube over a
flame?
a. Wearing long hair down
c. Pointing the test tube away from
b. Having safety goggles within reach
people
d. Keeping the test tube securely
stoppered
____ 38.
When the equation is correctly balanced, the coefficient of H2SO4 is —
a. 1
b. 2
c. 3
d. 4
____ 39. Which graph shows the relationship between temperature and volume as
described in Charles’ Law?
a. A
b. B
c. C
d. D
____ 40. Place the following models about the structure of the atom in the order that
they were developed:
1. Planetary model
2. Quantum mechanical model
3. Solid sphere model
a. 1, 3, 2
b. 1, 2, 3
c. 2, 3, 1
d. 3, 1, 2
____ 41. The boiling point of ethanol is 78.3C. The boiling point of ethanol on the
Kelvin scale is approximately —
a. 26 K
b. 178 K
c. 351 K
d. 451 K
____ 42.
The reaction is which type of chemical reaction?
a. Single replacement
b. Double replacement
____ 43. What does pH measure?
c. Synthesis
d. Decomposition
a. Hydrogen ion concentration
b. Hydroxide ion concentration
c. Acid density
d. Base density
____ 44.
The subscript of oxygen in the product should be —
a. 2
b. 5
c. 10
d. 20
____ 45. The proper scientific notation for 565,000,000,000 is —
A
B
C
D 565 109
12
a. 0.565 x 10
11
b. 5.65 x 10
10
c. 56.5 x 10
9
d. 565 x 10
____ 46. What are shared in covalent bonds?
a. Cations
b. Protons
c. Electrons
d. Anions
____ 47. A 0.67 L solution of ammonium sulfate, (NH4)2SO4, contains 0.81 mole of the
solute. What is the approximate molarity of the solution?
a. 0.54 M
b. 0.83 M
c. 1.2 M
d. 1.5 M
____ 48. Which of these is the percent of error in evaluating the molecular mass of a
compound if the experimental value was 105.2 amu and the known value was
107.5 amu?
a. 1.0%
b. 2.1%
c. 3.3%
d. 4.2%
____ 49. What is the correct formula for aluminum chloride?
a. AlCl3
b. Al3Cl
c. Al2Cl3
d. AlCl
____ 50.
NO2 and N2O4 undergo the reaction shown. When a sealed container of
reaches chemical equilibrium, which must be true?
a. No N2O4 is present.
c. The rates of the forward and reverse
reactions are equal.
No
chemical
reactions
are
occurring.
b.
d. The maximum number of molecules
has been reached.
Chem Sol 2007
Answer Section
MULTIPLE CHOICE
1. ANS: B
Read the bottom of the meniscus.
PTS: 1
2. ANS: D
Noble gases have their outer electron levels full. Other elements have a few more, or several less than a full 8
in their outer level.
PTS: 1
3. ANS: C
element
Ca
H
O
mass
multiple
40
1
16
1
2
2
sum
mass times
multiple
40
2
32
74
PTS: 1
4. ANS: C
Synthesis is when two elements form a compound.
PTS: 1
5. ANS: C
Elements in the same column have the same Lewis dot structure.
PTS: 1
6. ANS: B
40% of the pressure (800.0 mmHg) is from oxygen, so 320 mmHg
PTS: 1
7. ANS: B
12.5 moles C4H10
PTS: 1
8. ANS: D
Mn is manganese.
10 mol H2O
2 mol C4H10
62.5
Mg charge is 2+, Cl is 1swap charges for subscripts
MgCl2
PTS: 1
9. ANS: D
Ti atomic number is 22, so 22 protons and electrons
mass number is 50, so
neutrons is 50-22=28 neutrons
PTS: 1
10. ANS: A
Water is a polar molecule, therefore water molecules have a strong attraction for each other.
PTS: 1
11. ANS: D
Absolute zero is the temp at which molecules have no kinetic energy, they stop moving.
PTS: 1
12. ANS: A
Density =mass/volume
mass=density times volume
PTS: 1
13. ANS: B
16 g O2
1 mole O2
32 g O2
2 mole N2
5 mole O2
28 g N2
1 mole N2
5.6
PTS: 1
14. ANS: A
Chlorine and fluorine are both halogens, they both have -1 charge so they will have the same formula and
coefficients.
PTS: 1
15. ANS: D
Phosphorus is in CrOPS, so it has 4 oxygens in its “-ate” ion
Magnesium has only one charge(+2) so romans are not used.
PTS: 1
16. ANS: A
atomic number is protons, lower left of the isotope symbol
PTS: 1
17. ANS: D
Look at the data taken by each student 4 is consistently close the actual value. Student 1 is consistent but not
close the actual value.
PTS: 1
18. ANS: B
Kinetic theory states that:
weak forces between gas molecules
they are far apart
they travel in straight lines until they collide
collisions are elastic
PTS: 1
19. ANS: D
eliminate 12 and 13 since O is 16 g/mol
Be is 9 g/mol so BeO is 25 g/mol
PTS: 1
20. ANS: D
Catalysts decrease activation energy.
PTS: 1
21. ANS: C
chloride ion has -1 charge, use most common on chart, upper right of block on PT, top of list
charge = protons-electrons
charge = atomic number - electrons
electrons = atomic number - charge
chlorine atomic number is 17
chloride charge -1
e = Z - c = 17 - (-1) = 18
the element that has 18 electrons when neutral has 18 protons so Argon
PTS: 1
22. ANS: D
The bulb of the thermometer should be in the liquid, not touching sides or bottom.
PTS: 1
23. ANS: C
Periodic trends - electronegativity is decreasing down and increasing right...
So, less than 4.0 more than 2.8...
gotta be 3.0
PTS: 1
24. ANS: D
CaI2, NaCl, and KBr contain a metal and a non-metal, so they are ionic.
NO is the only one that has two non-metals, to make a covalent bond.
PTS: 1
25. ANS: C
5 moles C3H8
4 mole H2O
1 mole C3H8
6.02 x 1023
molecules
1 mole H2O
1.2 x 1025
four time as many moles of water form for every 1 mole of propane burned, so 20 moles of water form. each
has 6 x 1023 molecules in it.
PTS: 1
26. ANS: B
sublimation is solid to gas
PTS: 1
27. ANS: C
small electronnegativity difference results in electron sharing, ie covalent bonds.
PTS: 1
28. ANS: C
PTS: 1
29. ANS: C
mono means one oxygen
di means two oxygens
READ ALL THE RESPONSES CAREFULLY!
PTS: 1
30. ANS: D
Sodium Bicarbonate is baking soda, it forms a base when dissolved in water.
It will neutralize the acid.
PTS: 1
31. ANS: B
Isotopes of the same element differ by number of neutrons
PTS: 1
32. ANS: B
Looks like the relationship is linear, one point does not follow the general pattern, most likely due to
experimental error.
PTS: 1
33. ANS: C
P... 3=tri
N...5=penta
PTS: 1
34. ANS: D
molecule must be neutral
oxidation state = charge
+1 +(N) -2(3) = 0
must be +5
PTS: 1
35. ANS: A
Point 1 is the triple point where all three phases exist in equilibrium.
PTS: 1
36. ANS: A
Dalton’s Law says that the sum of partial pressures equals the total.
Pt=P1+P2+P3+P4+P5....
P(CO2)=Ptotal- all the other partials,
can’t be D
all the others = 593.44+7.10 = 600.54 +159.22= 759.76
so PCO2= 760.00-759.76=0.24 mm Hg
PTS: 1
37. ANS: C
Point it away in case it splatters.
PTS: 1
38. ANS: C
Balance it
Al coef is 2 (product subscript)
Al2(SO4)3 coefficient is 1
H2SO4 has 1 SO4 product side has 3 so coefficient is 3
PTS: 1
39. ANS: A
Charles Law is
V and T are directly related, when T goes up V goes up
Pressure is assumed constant in Charles’ Law
PTS: 1
40. ANS: D
Sphere, Democritus, Dalton
Planetary, Rutherford, Bohr
Quantum, Heisenberg et al
PTS: 1
41. ANS: C
K=C+273
K=78.3 + 273 = 351.3
PTS: 1
42. ANS: C
two become one = synthesis
PTS: 1
43. ANS: A
pH measures Hydrogen ion concentration [H+]
PTS: 1
44. ANS: B
There are 10 O’s on reactant side, so gotta be ten on the product side. With a coefficient of 2 that means it
needs to be 5.
PTS: 1
45. ANS: B
PROPER scientific means number has to be between 1 and 9 inclusive.
5.65 x 1011 is the only number written properly
PTS: 1
46. ANS: C
Bonding is all about ELECTRONS.
PTS: 1
47. ANS: C
M=moles/liters
M= 0.81/.67 = 0.81/(2/3) = 0.81 x (3/2) = 1.2 M
PTS: 1
48. ANS: B
has to be a little less than 2.3
so 2.1
PTS: 1
49. ANS: A
Al charge is +3
Cl charge is -1
swap charges for subscripts
PTS: 1
50. ANS: C
The mixture will reach and equilibrium where the rates of forward and reverse reactions are equal. The
amount of each will be constant.
PTS: 1