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Name: John Doe Title: Determination of Density Lab Exercise Materials and Equipment List: Equipment: Ruler Name: John Doe
Title: Determination of Density Lab Exercise
Materials and Equipment List:
Equipment: Ruler
10 mL graduated cylinder
100 mL graduated cylinder
Balance
Materials:
Water
Cooking oil
Salt (sodium chloride)
Marble
Quarter
AA battery
Cork
Procedure:
1. Various materials, such as coins, marbles, cork, vegetable oil, water, table
salt, and an AA battery were collected so that the density of the objects could be
measured. Except for the salt, water and oil all objects had regular shapes like
cylinders, spheres, or rectangular boxes.
2. For each solid object, a ruler was used to measure the dimensions in units of
centimeters. The dimensions of the objects were recorded and the volumes of the
objects were calculated from the formulas given in the laboratory handout.
3. In a second set of measurements, the volume of the solid objects was determined by
displacing water with them inside a graduated cylinder.
4. The mass of the solid objects was determined using the balance. The masses of the
various objects were recorded and used to calculate the density of the solid objects.

5. The mass of the salt, water and oil were obtained by measuring the mass of an
empty graduated cylinder using the balance. The mass of the empty cylinder was
recorded (mass 1). Then, for each liquid and also for the salt, some of the material was
poured into the clean and dry graduated cylinder. The mass of the cylinder with the
substance in it was recorded (mass 2) and the mass of the substance was computed by
subtracting the mass of the dry cylinder from the mass of the cylinder containing the
substance (mass 2-mass 1 = mass of substance). Measurements of the volume of the
liquids and the salt were read directly from the markings on the graduated cylinder. The
volume measurements for the oil, the water and the salt were then recorded. The
density of each liquid and the salt was calculated from the measured masses and
volumes. Results/Discussion:
Data collected for this experiment and calculated densities are shown in Table 1 below.
Table 1 - Mass, Volume and Calculated Density Information
Sample
Shape of
object
Mass (g)
Dimensions of
object (cm) and
Calculated or
measured
volume (cm
3
)
Estimated
volume by
displacement
method (mL)
Density of
sample using
calculated or
measured
volume (g/mL)
Density of
sample using
estimated
volume (g/mL)
Prediction of
whether the
sample should float
or sink (based on
density)
Does the
sample float
or sink?
(observed
behavior)
Cork
Cylinder
1.6225
r=1.011
h= 2.786
v=8.955
8.90
0.181
.0182
float
floats
Oil
N/A
9.1811
v=10.00
N/A
0.918
N/A
float
floats
Water
N/A
10.0219
v=10.00
N/A
1.002
N/A
N/A
N/A
Salt N/A
7.320
v=5.60
N/A
1.31
N/A
sink
sinks
Marble
Sphere
4.7891
r=0.793
v=2.09
1.93
2.29
2.48
sink
sinks
Battery
Cylinder
23.9607
r=0.700
h=4.925
v=7.58
7.70
3.16
3.11
sink
sinks
Quarters
(2)
Cylinder
11.3488
r=1.209
h=0.348
v=1.597
1.50
7.108
7.57
sink
sinks
The samples in Table 1 are ordered by increasing mass. Objects with a density
lower than the density of water should float. Objects with a density higher than the
density of water should sink. The experimental observation of whether an object should
sink or float are in agreement with the calculated densities for the objects. Table 2
(below) shows some typical, accepted values for several of the objects measured in the
experiment.
Table 2 - Accepted Values of Density for Selected Objects
Substance/object
Calculated
Density
(g/mL)
Accepted
Value of
Density (g/mL)
Reference Source
Cork (bark of cork oak tree)
0.181-0.182 0.10-0.25
Merck Index, 10
th
edition, 1983
Cooking Oil
0.918
.091-0.93
http://hypertextbook.com/facts/2000/IngaDorfman.shtml
Water
1.002
0.9975
Handbook of Chemistry and Physics 50
th
edition, 1969
Salt
1.31
2.2
Merck Index, 10
th
edition, 1983
Marble (mostly glass)
2.29-2.48
2.33-2.85
http://www.bd.com/accu-glass/materials.asp
Quarters (mostly copper)
7.108-7.57
8.92
Merck Index, 10
th
edition, 1983 As seen in Table 2, the experimentally obtained densities are close to the
accepted values for all substances except salt. The most likely reason the value for salt
disagreed with the accepted value is that we did not measure a large piece of salt. The
air pockets between the grains of salt have a much lower density than the salt resulting
in a much lower value for the density of salt when compared to the accepted value.
The calculated value of the density of the quarter is not particularly close to the
accepted value of copper (quarters are made primarily from copper). There may be
several reasons for the discrepancy. First, the outer jacket of a quarter not composed
of copper. Second, the copper in the quarter is probably an alloy (mixture of copper and
other metals) to make the copper harder so it doesnt bend easily. In addition, the
volume of the quarter cannot be accurately determined due to the irregular surfaces on
the faces of the coin. Small differences in the volume of the quarter result in relatively
large differences in the calculated density.
Overall, the experimental density values obtained agree nicely with accepted
values for many of the objects. Irregularly shaped objects had the largest deviations
from the accepted values. This is most likely due to uncertainty in the determination of
the volumes of these objects or uncertainty about the specific composition of the
irregularly shaped objects.