For an experiment, 9.7 mL of HCl are needed. What is

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Virginia Standards of Learning
Assessments
SOL
Scientific Investigation
For an experiment, 9.7 mL of HCl are
needed. What is the best instrument to
use for measuring this volume?
A
B
C
D
Beaker
Erlenmeyer flask
Graduated cylinder
Test tube
Which of the following pieces of
glassware can be used to measure the
volume of a liquid with the greatest
accuracy?
A
B
C
D
Test tube
Beaker
Flask
Graduated cylinder
To remove the sand first and then the
salt from a mixture of sand and salt
water, one combination of techniques
you could use would be to first —
A
B
C
D
evaporate and then distill
evaporate and then condense
filter and then evaporate
filter and then condense
A student used the ruler below to
measure the length of a nail. The length
of this nail, according to the precision of
the ruler, is —
A
B
C
D
3.5 cm
3.55 cm
3.7 cm
3.75 cm
Most gases have the property of becoming
increasingly soluble in a liquid as the temperature
of the liquid decreases. Which graph shows this
relationship?
Sig Figs
• How is 0.00124 expressed in proper
scientific notation?
•
A
1.24 x 10-3
•
B
0.124 x 10-2
•
C
1.24
•
D
1.24 x 103
The element chlorine exists as two naturally
occurring isotopes. Cl-35 occurs 75% of the
time and Cl-37 occurs 25% of the time. Which
of the following calculations should be used to
calculate the correct average atomic mass of
chlorine?
A student measures the mass of a piece of copper
three times and records the results in the following
table:
The actual mass of the copper
is 28.7 grams. Which of the
following is demonstrated in
the student’s data?
A
B
C
D
Accuracy
Continuity
Precision
Reliability
The mass of an object was recorded as
9.93 g, 9.90 g, and 10.02 g, using an
electronic analytical balance. What is the
average of these three masses expressed
to the correct number of significant
figures? 9.93 + 9.90 + 10.02 / 3 =
A
B
C
D
9.9 g
9.95 g
10.0 g
10.00 g
A student conducted an experiment and was
interested in the mass of the product of the chemical
reaction. Some results of the experiment are shown
above. What is the mass of the NaCl?
A
B
C
D
0.75 g
1.75 g
2.25 g
2.50 g
44.45 g
- 42.70 g
Measurement 1: 5.2 g
Measurement 2: 5.4 g
Measurement 3: 3 g
Measurement 4: 2.45 g
These data show repeated measurements
of the same object which has a known mass
of 5.38 grams. Which measurement is most
accurate?
A
1
B
2
C
3
D
4
A student wanted to calculate the formula for hydrated
copper sulfate. After careful massing, she heated the
compound to remove the water. She calculated the formula to
be CuSO4  4H2O. The actual formula was CuSO4  5H2O.
What is the most likely source of analytical error in the
student’s experiment?
A
B
C
D
The water was not completely evaporated from the
compound.
The actual mass of the anhydrous CuSO4 was less
than the measurement.
The CuSO4 reacted with elemental copper.
The atmospheric pressure prevented complete
reaction.
If a student’s hand is accidentally
exposed to an acidic solution, what
should be done?
A
B
C
D
Rinse the hand in a concentrated
base.
Rinse the hand in running
water.
Wrap the hand in paper
towels.
Cover the hand with oil.
What is the percentage of aluminum in
aluminum oxide (Al2O3)?
A
B
C
D
47%
48%
53%
54%
What is the percentage of aluminum in
aluminum oxide (Al2O3)?
Molar Mass of Al2O3 is
2(27.0) + 3(16.0) = 102 g
Mass of just Al is
2(27.0) = 54.0 g
54.0
Al % 
x100  53%
102 .0
What is the percentage of aluminum in
aluminum oxide (Al2O3)?
A
B
C
D
47%
48%
53%
54%
To determine the density of corn syrup, a student poured
3.0 mL of the liquid into a 10.0 mL graduated cylinder
and massed the cylinder and contents. He determined the
density to be 10.5 g/cm3. The accepted value for the
density of corn syrup is 1.38 g/cm3. The most probable
cause of error was that —
A
B
C
D
the mass and the volume were multiplied
the mass of the cylinder was included in the
density formula
the graduated cylinder accuracy is only 0.5 mL
the mass and volume were inverted in the
density formula
A student was instructed to carry out an experiment that
illustrates the law of conservation of mass. The teacher
indicated that the experiment should be carried out three
times. The student plans to report the average of the three
results. What can the student do to maximize the
reliability of the data collected?
A
B
C
D
Report the result that came closest to the class
average.
Conduct each trial using the same balance.
Report the average of the two most similar
values only.
Perform each of the trials on different days.
A chemical engineer for a fertilizer company is determining
the most efficient way to produce ammonia. The engineer
carries out the Haber reaction under four different
conditions. According to these data, which procedure gave the
greatest percent yield?
A
B
C
D
A
B
C
D
What is the Haber reaction?
1
N 2 ( g )  3H 2 ( g )  2 NH 3( g ) H  92KJmol
You do not need this
to solves the problem!
A chemical engineer for a fertilizer company is determining
the most efficient way to produce ammonia. The engineer
carries out the Haber reaction under four different
conditions. According to these data, which procedure gave the
greatest percent yield?
The one with the most!
A A
B B
C C
D D
According to the above data, which of the
following represents the average density for
sample X using the correct number of
significant figures?
A
1 g/mL
Hint: look at sigfigs in
data. The least
number is 2!
B
C
D
0.8 g/mL
0.81 g/mL
0.821 g/mL
At a constant volume, the pressure of a gas will
increase as the temperature increases. Which of the
following graphs shows that relationship?
A student must make a 3 M acid solution using a
5 M acid solution. Which of these is the safest way
to make the solution?
A
B
C
D
Slowly pour the 5 M acid into
water
Slowly add water to the 5 M
acid solution
Mix half the acid with water,
then add the remaining water
Mix half the water with the
acid, then add the remaining
acid
Which salt is most soluble in water at 90º C?
A
B
C
D
NaClO3
KNO3
KBr
NaCl
When examining the physical
properties of an unknown substance,
which of the following characteristics
is unsafe to observe?
A
B
C
D
Color
Weight
Form
Taste
The density of an unknown metal was
determined to be 2.85 g/mL. The actual
density was 2.70 g/mL. What is the percent
error in this determination?
A
0.056%
B
0.15%
C
5.6%
D
94.4%
| known  experiment al |
%E 
x
100

| 2.70known
 2.85 |
%E 
x100  5.6%
2.70
A student uses a mortar and pestle to crush 1.0 g of
marble chips and places them into a test tube. A whole 1.0
g marble chip is placed into a second test tube, and 5.0
mL of 6 M HCl is added to each test tube. The bubbling
speed of the produced CO2 gas is noted. This experiment
is designed to study the effect of the —
A
B
C
D
introduction of a catalyst on reaction rate
type of introduced acid on reaction rate
surface area of a reactant on reaction rate
temperature of a reactant on reaction rate
When CuSO4  5H2O is heated in a
crucible, there is a loss of water. How
should a student determine the amount of
water lost?
A
B
C
D
Subtract the mass of the CuSO4
from the mass of CuSO4  5H2O
Subtract the mass of the CuSO4 
5H2O from the mass of CuSO4
Add the masses of CuSO4  5H2O
and CuSO4
Multiply the masses of CuSO4  5
H2O and CuSO4
A student designed this experiment to study
the effects of a catalyst on a reaction. Which
trial serves as the experimental control?
A
B
C
D
1
2
3
4
Which of these shows a volume of 1.25
liters expressed in milliliters?
A
B
C
D
125 mL
12.5 x 101 mL
1.25 x 102 mL
1.25 x 103 mL
A student spills a diluted acid solution
on his hand. He should —
A
B
C
D
wipe it off with a paper
towel
let it air dry
apply a base solution to
neutralize it
rinse it off with running
water
A student wanted to obtain a very accurate value for the
volume of a piece of steel. He filled a 100.0 cm3 graduated
cylinder to the 50.0 cm3 mark with water. After he
carefully dropped the steel into the cylinder, the water
level rose to the 55.6 cm3 level. He reported the volume of
the steel as 5.6 cm3. How could the student improve the
reliability of his analysis?
A
B
C
D
Report the volume as 56 mm3
Fill the graduated cylinder to the 70.0 cm3
mark
before adding the steel
Mass the steel and report its density in
g/cm3
Repeat the measurement many times and
report an average value
If a student needed to obtain 8.0 mL of
a liquid for an experiment, the
appropriate piece of laboratory
equipment to use would be a —
A. 50 mL beaker
B. 1.0 mL pipet
C. 50 mL flask
D. 10.0 mL graduated cylinder
If a lab group
were using
hydrochloric acid
to perform a
substitution
reaction, which
precaution would
not be a concern?
If a lab group were using hydrochloric
acid to perform a substitution
reaction, which precaution would not
be a concern?
A. Flammability
B. Health
C. Reactivity
D. Contact
Which of the following best describes
why an experiment should be
repeated?
A. To organize the data
B. To produce a variety of results
C. To include another variable
D. To verify the observed results
The graph shows the rate of a certain reaction as a
function of temperature. According to the graph,
in order to double the rate of the reaction at 20° C,
the temperature must be increased by
approximately —
A. 10° C
B. 20° C
C. 30° C
D. 40° C
A student obtained these data after
measuring the mass of an object three
different times. If the true value of the
object’s mass is 5.550 g, these data are
best described as —
• First measurement: 6.293 g
• Second measurement: 6.294 g
• Third measurement: 6.295 g
A student obtained these data after
measuring the mass of an object three
different times. If the true value of the
object’s mass is 5.550 g, these data are
best described as —
A. precise but not accurate
B. accurate but not precise
C. accurate and precise
D. neither accurate nor precise
A team of chemistry students made the
above measurements and density
calculations of the same type of material.
The accepted value (true value) of the
density of the material is 5.72 g/cm3. Which
trial has the least amount of absolute error?
The accepted value (true value) of the
density of the material is 5.72 g/cm3. Which
trial has the least amount of absolute
error?
m Which trial is closest to 5.72?
A. 1
B. 2
C. 3
D. 4
D
V
The figure shows an experimental
setup used to separate the components
of a colored ink sample. Which of the
following describes this laboratory
technique?
A. Chromatography
B. Filtration
C. Decanting
D. Distillation
Which basic lab technique involves the
separation of a mixture’s components
through differences in particle size?
A. Filtration
B. Extraction
C. Distillation
D. Crystallization
The graph shows the
pressure of an ideal gas as
a function of its volume.
According to the graph,
increasing the volume
from 100 mL to 150 mL
—
A. decreases the pressure by 80 kPa
B. decreases the pressure by 160 kPa
C. increases the pressure by 80 kPa
D. increases the pressure by 160 kPa
How should 0.000365 be expressed
in proper scientific notation?
A. 3.65 X 104
B. 365
C. 3.65
D 3.65 X 10-4
SIG FIGS
• The reaction times for three trials of an
experiment are 90.3, 90.2, and 90.5
seconds. Which average time is expressed
using the correct number of significant
figures?
A. 90.3
B. 90.33
C. 90
D. 90.333
What is the name of the
lab equipment
shown ?
A. Watch glass
B. Crucible
C. Beaker
D. Evaporating dish
The melting point of a white solid
substance was determined in four
repeated trials to be 56.0° C, 55.0° C,
57.5° C, 55.5° C. What temperature
should be reported as the melting
point as a result of these trials?
A. 55.0° C
B. 55.5° C
C. 56.0° C
D. 57.5° C
56.0 + 55.0 + 57.5 + 55.5 = 224/4 = 56.0o C
Which is the best indicator for giving a
color change at the equivalence point?
A. Bromocresol green
B. Indigo carmine
C. Neutral red
D. Phenolphthalein
Methyl mercury, found in some stream
sediments, is highly toxic to animal life.
Using the graphed results of the study
shown, the best analysis of the data reveals
that the methyl mercury concentration in the
stream sediment is —
Using the graphed results of the study
shown, the best analysis of the data reveals
that the methyl mercury concentration in the
stream sediment is —
A. steadily increasing, accelerating in the fall
of each year
B. increasing overall but reaches a minimum
in the winter
C. constantly declining throughout each month
of the year
D. decreasing but reaches a maximum at the
end of summer
What is a possible cause of a large percentage
of error in an experiment where MgO is
produced from the combustion of magnesium?
Hint: eliminate choices!
A. Not all of the Mg has completely reacted.
B. The same balance was used throughout the
experiment.
C. The students were careful in their
measurements.
D. The students were careful not to spill the
contents.
The volume of Object X is approximately —
A. 20 mL
B. 25 mL
C. 30 mL
D. 35 mL
V = 90 – 65 = 25
The following data were collected.
The volume of the gas is known to be
2.20 L.
This data reflects —
A. low precision and low
accuracy
B. low precision and high
accuracy
C. low accuracy and high
precision
D. high accuracy and high
precision
2C4H10 + 13O2  8CO2 + 10H2O
What is the mole ratio of C4H10 to
CO2 in the reaction shown?
A. 1:4
B. 2:13
C. 4:5
D. 13:8
YAHOO FINISHED!
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