Density of Elements Lab
Name: _________________________
Date: _________________________
Lab Partners: ______________________________
______________________________
______________________________
______________________________
Prelab Discussion:
Today, you will be determining the density of copper, zinc, and lead. Density is a physical
property that describes the relationship between the amount of matter (mass) an object contains for an
amount of space it takes up (volume). Its formula is:
D = m/v (where m = mass and v = volume)
A substance whose density is 10g/ml has twice the amount of matter for the same amount of space as
one with a density of 5g/ml.
Objective: (In your lab report, be sure to describe what we want to learn &/or prove)
Upon completing this lab investigation, you will be able to determine the mass, volume, and
densities of copper, zinc, and lead. You will also be able to determine the percent error of your
calculations when compared to the standard (actual) value.
Materials:
- Samples of copper, zinc and lead
- 100 mL graduated Cylinder (this will help me determine the _______ of the substance.)
- Scale (this will help me determine the _______ of the substance.)
- Water
Safety:
-
No horseplay
Clean up spills ASAP
Procedure: (In your lab report, be sure to write the procedures in your own words and number
them)
1.
2.
3.
4.
5.
6.
7.
10.
11.
12.
13.
Each group should obtain a 100 mL graduated cylinder.
Fill the graduated cylinder with 15 mL of water. (Record on Data Table)
Obtain a sample of copper.
Turn on the electronic balance and make certain that the balance is measuring grams (g).
Place the sample of the copper on the balance.
Determine the mass of the copper. (Record on Data Table)
Place the copper sample into the graduated cylinder.
Record the Final (new) volume of the water.(Record on Data Table)
Calculate the volume of the copper only. (Record on Data Table)
Calculate the density of the copper. (Record on Data Table)
Use the Percent Error formula to determine your accuracy compared to the actual value. (Record
on Data Table)
14. Pour off the water and return the sample to where your teacher designates.
Determining density of zinc and lead
15. Perform the same steps for a sample of zinc and lead
Data Table (In your lab report, be sure to provide a copy of this chart)
Graduated Graduated Volume
Cylinder - Cylinder of
Initial
Final
substance
Volume
Volume
(mL)
(mL)
(mL)
Mass of
substance
(g)
Observed
Density of
substance
(g/mL)
Actual
Density of
each
substance
(g/mL)
% Error
(%)
Zinc
7.134
Copper
8.960
Lead
11.300
Calculations: (In your lab report, be sure to show your calculations)
Useful formulas:
D = m/v (where D= density, m = mass and v = volume)
Observed Value – Accepted Value
% Error = -------------------------------------------------------- (100)
Accepted Value
Questions: (In your lab report, be sure to write complete sentences)
1. Assume you doubled the amount of copper you used in the lab. What would happen to it’s:
(HINT – before you answer this, create some factitious numbers and use the density formula)
Mass? ____________
Volume? _____________
Density? _____________
2. What are some sources for error? (Identify at least 2)
3. If you were to change these solid samples to liquid, what would happen to its:
Mass? ____________
Volume? _____________
Density? _____________
4. Thinking about the skills you developed in this lab, if someone gave you some pure gold, what can
you do determine if their claim is true?
Conclusion: Be sure your conclusion relates to the objective and follows the Rubric provided.