Directions: record rough drafts of the lab (Q, H, T, M, P
w/diagram & D) individually into your science notebook. The final draft will include writing a Lab
write up, according to the supplied rubric for Lab Writeups, in a Microsoft
Word document with data analysis completed using Microsoft Excel and inserted
into the Lab Writeup.
Question: How Can the density of minerals be accurately determined (within 10%)
by measuring their volume and mass using a graduated cylinder and a metric
balance?
Hypothesis: Through the use of water displacement to
determine volume and using a metric balance, students will be able to accurately
(within 10%) determine the density of known mineral samples.
Test: Hint:
Use the question, test and materials to design a brief one or two sentence
statement of how you will find the density of the mineral samples and compare
them to accepted values provided by your teacher.
Materials: 100 ml
graduated cylinder, metric balance, water supply, unknown mineral samples,
paper towel and any other materials you use Milky Quartz, Galena,
Magnetite, Calcite and Hematite samples
Procedures: Work with
your group mates to determine how you will collect data using each material to
conduct the experiment. Your procedures
should be descriptive step by step instructions which include a diagram that
will visually illustrate the more complex procedural steps. Remember that Density (D) = Mass (m) / Volume
(v) and should be in g/cm^{3}.
Data Table: Construct in your
notebook, place data collected there.
Physical
Description of Mineral

Measured
mass in g

Measured
volume in cm^{3}
(1ml =1cm^{3})

Calculated
Density in
g/cm^{3}

Name of
mineral


























Observations of
data collection: Write these
descriptions in your notebook
Analysis:
 Gather the calculated density for each other sample from the
other groups in class. Determine
the average class density for each mineral and be sure to show how you
made the calculations.
 Make a bar graph that compares the ave.
calculated density of each mineral sample to the accepted density of the
samples provided by your teacher.
Graph the mineral samples from least dense to most dense. Include a
diagram of how these samples should be found, according to their
densities, if they where all in the same area of the crust.
 If the group average density is different from the accepted
densities (greater than 10%) describe the possible errors that might have
led to these differences.
 Find % error for you class ave. of each mineral using the
formula: {accepted – experimental /accepted} X 100%, where brackets
indicate to take an absolute value.
Conclusion:
The following are prompts to help you write a
conclusion. Write you conclusion using
complete sentences and the rubric.
Frame work: Were you
able to identify the unknown minerals by calculating their density? If not, how did you ID the samples? i.e what
other factors did you use to identify your mineral samples? Evidence:
Compare the accuracy of your density calculations to the accepted
densities. Error: How did error influence your calculated
densities? Logic: How do the experimental mineral densities
compare to the actual densities? Next
Step: What could be done to improve
or further investigate this experiment?
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