Mr. Murdoch
Unit 1, 2 & 3 Exam Practice
Reg Chem '14 to '15
These 49 questions came from NYS Chemistry Regents Exams. These 49 questions are similar to
the TYPES of questions you will have on your Unit 1, 2, & 3 Chemistry Exam on Wednesday,
October 29th 2014. The answer key for these 49 questions will be posted on Mr. Murdoch's
Chemistry website.
1. A student intended to make a salt solution with a
concentration of 10.0 grams of solute per liter of
solution. When the student’s solution was
analyzed, it was found to contain 8.90 grams of
solute per liter of solution. What was the percent
error in the concentration of the solution?
1) 1.10%
3) 11.0%
5. The diagram below represents a Celsius
thermometer recording a certain temperature.
2) 8.90%
4) 18.9%
2. A student calculated the percent by mass of water
in a hydrate as 14.2%. A hydrate is a compound
that contains water as part of its crystal structure.
If the accepted value is 14.7%, the student's
percent error was
1)
2)
3)
4)
3. Which mass measurement contains four
significant figures?
1) 0.086 g
3) 1003 g
2) 0.431 g
4) 3870 g
4. Expressed to the correct number of significant
figures, the sum of two masses is 445.2 grams.
Which two masses produce this answer?
1)
2)
3)
4)
210.10 g + 235.100 g
210.100 g + 235.10 g
210.1 g + 235.1 g
210.10 g + 235.10 g
What is the correct reading of the thermometer?
1) 5°C
3) 0.3°C
2) 4.3°C
4) 4°C
6. During a laboratory activity, a student combined
two solutions. In the laboratory report, the
student wrote “A yellow color appeared.” The
statement represents the student’s recorded
1) conclusion
3) hypothesis
2) observation
4) inference
7. When a mixture of water, sand, and salt is
filtered, what passes through the filter paper?
1)
2)
3)
4)
Unit 1-3 Exam Practice
Page 1
water, only
water and sand, only
water and salt, only
water, sand, and salt
Unit 1, 2 & 3 Exam Practice
8. Which mixture can be separated by using the
equipment shown below?
10. Given the diagrams X, Y, and Z below:
Which diagram or diagrams represent a mixture
of elements A and B?
1) X, only
3) X and Y
2) Z, only
4) X and Z
11. Which of these contains only one substance?
1)
2)
3)
4)
NaCl(aq) and SiO2(s)
NaCl(aq) and C 6H12O6(aq)
CO 2(aq) and NaCl(aq)
CO 2(aq) and
C6H12O6(aq)
9. A dry mixture of KNO3 and sand could be
separated by
1)
2)
3)
4)
adding water to the mixture and filtering
adding water to the mixture and evaporating
heating the mixture to a high temperature
cooling the mixture to a low temperature
1) distilled water
3) saltwater
2) sugar water
4) rainwater
12. Which of these terms refers to matter that could
be heterogeneous?
1) element
3) compound
2) mixture
4) solution
13. One similarity between all mixtures and
compounds is that both
1)
2)
3)
4)
are heterogeneous
are homogeneous
combine in a definite ratio
consist of two or more substances
14. Which sample of matter is classified as a
solution?
1) H2O(s)
3) CO 2(g)
2) H2O( )
4) CO 2(aq)
15. According to Reference Table H, what is the
vapor pressure of propanone at 45°C?
1) 22 kPa
3) 70 kPa
Unit 1-3 Exam Practice
Page 2
2) 33 kPa
4) 98 kPa
Unit 1, 2 & 3 Exam Practice
16. As the temperature of a liquid increases, its
vapor pressure
22. A gas occupies a volume of 40.0 milliliters at
20°C. If the volume is increased to 80.0
milliliters at constant pressure, the resulting
temperature will be equal to
1) decreases
2) increases
3) remains the same
17. Based on Reference Table H, which sample has
the highest vapor pressure?
1) water at 20ºC
3) ethanol at 50ºC
2) water at 80ºC
4) ethanol at 65ºC
2)
3)
4)
23. Which graph shows the pressure-temperature
relationship expected for an ideal gas?
18. Which sample of water has the lowest vapor
pressure?
1) 100 mL at 50ºC
3) 300 mL at 40ºC
1)
1)
2) 200 mL at 30ºC
4) 400 mL at 20ºC
19. The freezing point of bromine is
1) 539°C
3) 7°C
2) –539°C
4) –7°C
2)
20. In which equation does the term "heat"
represent heat of fusion?
1) NaCl(s) + heat
NaCl( )
2) NaOH(aq) + HCl(aq)
NaCl(aq) + H 2O(
) + heat
3) H2O( ) + heat
H2O(g)
4) H2O( ) + HCl(g)
H3O+ (aq) + Cl–(aq) +
heat
3)
21. The graph below represents the heating curve of
a substance that starts as a solid below its
freezing point.
4)
24. A 3.00-liter sample of gas is at 288 K and 1.00
atm. If the pressure of the gas is increased to
2.00 atm and its volume is decreased to 1.50
liters, the Kelvin temperature of the sample will
be
What is the melting point of this substance?
1) 30°C
3) 90°C
Unit 1-3 Exam Practice
1) 144 K
3) 432 K
2) 55°C
4) 120°C
Page 3
2) 288 K
4) 576 K
Unit 1, 2 & 3 Exam Practice
25. Which temperature change would cause the
volume of a sample of an ideal gas to double
when the pressure of the sample remains the
same?
1)
2)
3)
4)
30. A real gas differs from an ideal gas because the
molecules of real gas have
1) some volume and no attraction for each
other
2) some volume and some attraction for
each other
3) no volume and no attraction for each other
4) no volume and some attraction for each
other
from 200ºC to 400ºC
from 400ºC to 200ºC
from 200 K to 400 K
from 400 K to 200 K
26. As the temperature of a gas increases at constant
pressure, the volume of the gas
31. Two basic properties of the gas phase are
1) decreases
2) increases
3) remains the same
1)
2)
3)
4)
27. At the same temperature and pressure, 1.0 liter
of CO(g) and 1.0 liter of CO2(g) have
1) equal masses and the same number of
molecules
2) different masses and a different number of
molecules
3) equal volumes and the same number of
molecules
4) different volumes and a different number of
molecules
28. A closed container holds 3.0 moles of CO 2 gas
at STP. What is the total number of moles of
Ne(g) that can be placed in a container of the
same size at STP?
1) 1.0 mole
3) 3.0 moles
32. An increase in the average kinetic energy of a
sample of copper atoms occurs with an increase
in
1) concentration
3) pressure
2) temperature
4) volume
33. Which change in the temperature of a 1-gram
sample of water would cause the greatest
increase in the average kinetic energy of its
molecules?
1) 1°C to 10°C
3) 50°C to 60°C
2) 10°C to 1°C
4) 60°C to 50°C
34. A sealed flask containing 1.0 mole of H 2(g) and
a sealed flask containing 2.0 moles of He(g) are
at the same temperature. The two gases must
have equal
2) 1.5 moles
4) 0.0 moles
29. A real gas behaves more like an ideal gas when
the gas molecules are
1) close and have strong attractive forces
between them
2) close and have weak attractive forces
between them
3) far apart and have strong attractive forces
between them
4) far apart and have weak attractive forces
between them
Unit 1-3 Exam Practice
a definite shape and a definite volume
a definite shape but no definite volume
no definite shape but a definite volume
no definite shape and no definite volume
Page 4
1)
2)
3)
4)
masses
volumes
average kinetic energies
numbers of molecules
Unit 1, 2 & 3 Exam Practice
35. A student determines the density of zinc to be
7.56 grams per milliliter. If the accepted density
is 7.14 grams per milliliter, what is the student’s
percent error?
• Show a correct numerical setup.
• Record your answer.
36. A student used a balance and a graduated cylinder to collect the following data:
a Calculate the density of the element. Show your work. Include the appropriate number of
significant figures and proper units.
b If the accepted value is 6.93 grams per milliliter, calculate the percent error.
c What error is introduced if the volume of the sample is determined first?
37. Base your answers to the following questions on the information below.
A hot pack contains chemicals that can be activated to produce heat. A cold pack contains
chemicals that feel cold when activated.
a Based on energy flow, state the type of chemical change that occurs in a hot pack.
b A cold pack is placed on an injured leg. Indicate the direction of the flow of energy
between the leg and the cold pack.
c What is the Law of Conservation of Energy? Describe how the Law of Conservation of
Energy applies to the chemical reaction that occurs in the hot pack.
38. Base your answer to the following question on
the information below.
Given the equation for the dissolving of sodium
chloride in water:
When NaCl(s) is added to water in a
250-milliliter beaker, the temperature of the
mixture is lower than the original temperature of
the water. Describe this observation in terms of
heat flow.
Unit 1-3 Exam Practice
Page 5
Unit 1, 2 & 3 Exam Practice
Base your answers to questions 39 through 42 on the information below.
Given the heating curve where substance X starts as a solid below its melting point and is
heated uniformly:
39. Describe, in terms of particle behavior or energy, what is happening to substance X during
line segment
.
40. Using (•) to represent particles of substance X, draw at least five particles as they would
appear in the substance at point F. Use the box provided above.
41. Identify a line segment in which the average kinetic energy is increasing.
42. Identify the process that takes place during line segment DE of the heating curve.
Unit 1-3 Exam Practice
Page 6
Unit 1, 2 & 3 Exam Practice
Base your answers to questions 43 and 44 on the
diagram below, which shows a piston confining
a gas in a cylinder.
43. The gas volume in the cylinder is 6.2 milliliters
and its pressure is 1.4 atmospheres. The piston
is then pushed in until the gas volume is 3.1
milliliters while the temperature remains
constant.
a Calculate the pressure, in atmospheres, after
the change in volume. Show all work.
b Record your answer.
44. Sketch the general relationship between the
pressure and the volume of an ideal gas at
constant temperature.
45. a Calculate the heat released when 25.0 grams
of water freezes at 0°C. Show all work.
b Record your answer with an appropriate unit.
Unit 1-3 Exam Practice
Page 7
Unit 1, 2 & 3 Exam Practice
Base your answers to questions 46 through 48 on the graph below, which shows the vapor
pressure curves for liquids A and B.
46. Which liquid will evaporate more rapidly? Explain your answer in terms of intermolecular
forces.
47. At what temperature does liquid B have the same vapor pressure as liquid A at 70°C? Your
answer must include correct units.
48. What is the vapor pressure of liquid A at 70°C? Your answer must include correct units.
Unit 1-3 Exam Practice
Page 8
Unit 1, 2 & 3 Exam Practice
49. A sample of water is heated from a liquid at 40°C to a gas at 110°C. The graph of the heating
curve is shown below.
a. On the heating curve diagram provided below, label each of the following regions:
Liquid, only
Gas, only
Phase change
b. For section QR of the graph, state what is happening to the water molecules as heat is
added.
c. For section RS of the graph, state what is happening to the water molecules as heat is
added.
Unit 1-3 Exam Practice
Page 9
Unit 1, 2 & 3 Exam Practice
Unit 1-3 Exam Practice
Page 10
Chemistry[Chem Un 1 to 3 practice[10/26/2014]]- Eduware Classification
11.LABS AND MEASUREMENTS (8)
11.A.Labs and Measurements (6)
11.A.ii.Measurement and Equipment (5)
11.A.ii.c.Percent Error (2)
11.A.ii.b.Significant Figures / Metric Units (3)
11.A.i.Scientific Methods (1)
11.B.Constructed Response XI (2)
5.PHYSICAL BEHAVIOR OF MATTER (40)
5.F.Mixtures (8)
5.F.ii.Separation of Mixtures (3)
5.F.ii.a.Filtration (3)
5.F.i.Homogeneous / Heterogeneous (5)
5.E.Intermolecular Forces (4)
5.E.ii.Vapor Pressure and Evaporation (4)
5.D.Phase Changes (3)
5.D.v.Boiling, Evaporating, Heat of Vaporization (1)
5.D.iv.Melting, Heat of Fusion / Solid (1)
5.D.i.Heating / Cooling Curves (1)
5.C.Properties of Gases (10)
5.C.ii.Gas Laws (7)
5.C.ii.b.Combined Gas Law Problems (5)
5.C.ii.a.Avogadro's Hypothesis (2)
5.C.i.Ideal Gas Model (KMT) (3)
5.C.i.b.Real Gas Deviations (2)
5.C.i.a.Ideal Gas Theory (1)
5.B.Energy, Temperature & Entropy (3)
5.B.ii.Temperature (3)
5.B.ii.a.Average Kinetic Energy (3)
5.H.Constructed Response V (12)
6.KINETICS/EQUILIBRIUM (1)
6.E.Constructed Response VI (1)
Total Questions: 49
Exam Question Summary
Unit 1-3 Exam Practice
Chem Un 1 to 3 practice
10/26/2014
#
QID# Ans Thinking Skills Standards
1
5044
3
11.A.ii.c.
2
4896
3
11.A.ii.c.
3
4905
3
11.A.ii.b.
4
4856
3
11.A.ii.b.
5
4855
2
11.A.ii.b.
6
4968
2
11.A.i.
7
5022
3
5.F.ii.a.
8
4940
1
5.F.ii.a.
9
4858
1
5.F.ii.a.
10
5197
2
5.F.i.
11
5172
1
5.F.i.
12
5090
2
5.F.i.
13
5017
4
5.F.i.
14
4819
4
5.F.i.
15
5115
3
5.E.ii.
16
4963
2
5.E.ii.
17
4800
4
5.E.ii.
18
4743
4
5.E.ii.
19
5116
4
5.D.v.
20
4957
1
5.D.iv.
21
5048
2
5.D.i.
22
5046
3
5.C.ii.b.
23
4872
1
5.C.ii.b.
24
4820
2
5.C.ii.b.
25
4803
3
5.C.ii.b.
26
4798
2
5.C.ii.b.
Page 12
Exam Question Summary
Unit 1-3 Exam Practice
Chem Un 1 to 3 practice
10/26/2014
#
QID# Ans Thinking Skills Standards
27
5174
3
5.C.ii.a.
28
4772
3
5.C.ii.a.
29
5170
4
5.C.i.b.
30
4802
2
5.C.i.b.
31
4746
4
5.C.i.a.
32
5013
2
5.B.ii.a.
33
4874
3
5.B.ii.a.
34
4745
3
5.B.ii.a.
35
5218
n/a
11.B.
36
4995
n/a
11.B.
37
4922
n/a
6.E.
38
5221
n/a
5.H.
39
5214
n/a
5.H.
40
5213
n/a
5.H.
41
5212
n/a
5.H.
42
5211
n/a
5.H.
43
5140
n/a
5.H.
44
5139
n/a
5.H.
45
5137
n/a
5.H.
46
5071
n/a
5.H.
47
5070
n/a
5.H.
48
5069
n/a
5.H.
49
4987
n/a
5.H.
Page 13
Answer Key
Chem Un 1 to 3 practice
1.
1
2.
1
3.
1
4.
1
5.
1
6.
1
7.
1
2
2
2
2
2
2
2
3
3
3
3
3
3
3
4
19.
1
4
20.
1
2
3
4
4
21.
1
2
3
4
4
22.
1
2
3
4
4
23.
1
2
3
4
4
24.
1
2
3
4
4
25.
1
2
3
4
26.
1
2
3
27.
1
2
3
4
28.
1
2
3
4
8.
1
2
3
4
9.
1
2
3
4
10.
1
2
3
4
11.
1
2
3
4
12.
1
2
3
4
13.
1
2
3
4
14.
1
2
3
4
15.
1
2
3
4
16.
1
2
3
17.
1
2
3
4
18.
1
2
3
4
36.
2
3
39.
4
or,
29.
1
2
3
4
30.
1
2
3
4
31.
1
2
3
4
32.
1
2
3
4
33.
1
2
3
4
34.
1
2
3
4
or,
and accept only to
the nearest tenth
with a range from
6.7 - 6.9
Proper Units: g/ml
or grams per
milliliter
b) Range of 1.8 2.0%
c) The density
would increase
because the
sample was wet
when weighed
37.
(essay)
38.
Examples: –An
endothermic
process absorbs
heat energy.
–Heat flows from
the surroundings
to the mixture.
–heat is absorbed
by system
Examples: –The
potential energy of
the particles
increases. –PE
increases.
–KE remains the
same. –particles
more disordered
–Particles are
spreading farther
apart.
–Intermolecular
forces of attraction
decrease.
40.
41.
Examples:
or
or
42.
Examples:
–boiling
–vaporization
–liquid – vapor
equilibrium
43.
a Example: (6.2
mL)(1.4 atm) =
(3.1 mL)(P 2)
b 2.8
44.
45.
35.
Unit 1-3 Exam Practice
a) Examples:
Examples: 5.88
or 5.9 or 6
Page 14
a Examples: q =
mH f = (25.0
g)(334 J/g) or
25.0(334)
b 8350 J
Answer Key
Chem Un 1 to 3 practice
46.
liquid A
Example:
The higher vapor
pressure of liquid
A indicates that the
intermolecular
forces between its
molecules are
weaker, allowing
the molecules to
escape more
readily to the
vapor phase.
47.
114 (±2) °C
48.
710 (±10) mm Hg
49.
(essay)
Unit 1-3 Exam Practice
Page 15
Question ID's in
Numerical Order
9. 4858
10. 5197
18. 4743
34. 4745
31. 4746
28. 4772
26. 4798
17. 4800
30. 4802
25. 4803
14. 4819
24. 4820
5. 4855
4. 4856
23. 4872
33. 4874
2. 4896
3. 4905
37. 4922
8. 4940
20. 4957
16. 4963
6. 4968
49. 4987
36. 4995
32. 5013
13. 5017
7. 5022
1. 5044
22. 5046
21. 5048
48. 5069
47. 5070
46. 5071
12. 5090
15. 5115
19. 5116
45. 5137
44. 5139
43. 5140
29. 5170
11. 5172
27. 5174
42. 5211
41. 5212
40. 5213
39. 5214
35. 5218
38. 5221
Answer Key
Chem Un 1 to 3 practice
37.
a exothermic
b Examples: – Energy flows from the injured leg to the cold pack. – Heat flows from the higher
temperature (the leg) to the lower temperature (the cold pack). – The cold pack absorbs heat
energy from the injured leg.
c – The energy released from the hot pack is equal to the energy absorbed by the surroundings. –
The total energy of the system (the hot pack) is equal to the total energy of the surroundings. –
Everything else is constant.
49.
b. Examples: –The water molecules acquire more kinetic energy. –Heat is converted to kinetic
energy of the water molecules. –The water molecules speed up or increase their relative motion.
c. Examples: –The potential energy of the water molecules increases. –The water molecules
change from the liquid phase to the gas phase. –There is less attraction between the H 2O
molecules.