How to find unknown volumes and densities
Define: Mass, Volume, Density Mass The amount of matter something has What is matter? Measured in pounds Volume The amount of space something takes up Density Amount of matter PER space
How do they relate?
Practice Mass = 20 pounds Volume = 10 Liters What is the Density of this object?
Archimedes Ancient Greek mathematician, engineer, inventor, and astronomer Born in Syracuse, Italy – lived to be 75 King Hieron II approached Archimedes 2200 years ago
Practice problems – find volume What is the density of 14 mL of liquid substance with a mass of 2.6 grams?
find Density
Finding Density Lab Each lab group has been assigned an unknown solid The purpose of this lab is to identify your unknown
Things you will need: Unknown object Graduated Cylinder Water in Graduated Cylinder Triple Beam Balance Calculator Lab Report Sheet
Lab Report Fill in your materials list, your purpose, and your hypothesis As we complete each step in this lab, fill each one in the procedure section in great detail As we complete each step fill in the data/observations/results section
Procedure Weigh your unknown object AND RECORD THE WEIGHT Record the volume of the water in the graduated cylinder Submerse the unknown object into the graduated cylinder and record the new volume of the water Find the volume of your object AND RECORD IT Using the volume and the mass, find the density (remember the formula we use for this) Compare the density your group found with the densities posted on the board in order to identify your unknown substance
Observations How did you find the volume of your object? How did you find the density of your object? What unknown substance did your group have? Did any other groups have that substance? Did the volume of the substance change the density of it?
Conclusions What did we learn from this lab? Can we now successfully identify an unknown metal or element? Where could we find this list of densities to identify metals with if they were not given to us?