AP phyiscs lab
Density Lab January 24, 2014
Benjamin
I. Purpose- The purpose of this lab is to identify the unknown substances by calculating the densities of the given substances then comparing those densities to the actual densities on the table given.
II. Materials-
Graduated cylinders
Triple beam balance
Unknown substances from bag given by teacher
Table of known densities
Calculator
Water
III. Procedure- The first thing one must do to identify which substance is which is to calculate the densities. To do this, one must take the mass and volume of each individual substance. Starting with mass, one can use the triple beam balance. Make sure the balanced is zeroed. Once that is true, place the object onto the balance a carefully find the mass of the object. Repeat and record the results found of each individual substance. To find the volume, one can use the water displacement method. One will fill up a graduated cylinder with water to a specific amount. 20 mL is sufficient. Once completed, one will drop one of the substances into the graduated cylinder and record how far the water level rises. If it starts at 20mL and rises to 22mL then the volume of the substance is 22mL minus 20mL, so 2mL. Repeat and record the results found of each individual substance.
Once all of the data is recorded one will have to find the densities from their data. To do this one will have to know the formula to calculate density. This formula is p=m/v. Density is equal to mass divided by volume. One will use a calculator to divide the mass they found by the volume they found. With the newly calculated densities one must compare their calculated densities to the known densities on the data table and record the results.
IV. Data-
Substances
Mass
Volume
Calculated Density
Cork
.15g
.3mL
.5g/mL
Marble
3.85g
1mL
3.85g/mL
Gold rod
8.6g
1mL
8.6g/mL
Copper rod
9.05g
1mL
9.05g/mL
White rod
1.15g
1mL
1.15g/mL
Matte gray rod
1.5g
1mL
1.5g/mL
Matte silver
Benjamin
I. Purpose- The purpose of this lab is to identify the unknown substances by calculating the densities of the given substances then comparing those densities to the actual densities on the table given.
II. Materials-
Graduated cylinders
Triple beam balance
Unknown substances from bag given by teacher
Table of known densities
Calculator
Water
III. Procedure- The first thing one must do to identify which substance is which is to calculate the densities. To do this, one must take the mass and volume of each individual substance. Starting with mass, one can use the triple beam balance. Make sure the balanced is zeroed. Once that is true, place the object onto the balance a carefully find the mass of the object. Repeat and record the results found of each individual substance. To find the volume, one can use the water displacement method. One will fill up a graduated cylinder with water to a specific amount. 20 mL is sufficient. Once completed, one will drop one of the substances into the graduated cylinder and record how far the water level rises. If it starts at 20mL and rises to 22mL then the volume of the substance is 22mL minus 20mL, so 2mL. Repeat and record the results found of each individual substance.
Once all of the data is recorded one will have to find the densities from their data. To do this one will have to know the formula to calculate density. This formula is p=m/v. Density is equal to mass divided by volume. One will use a calculator to divide the mass they found by the volume they found. With the newly calculated densities one must compare their calculated densities to the known densities on the data table and record the results.
IV. Data-
Substances
Mass
Volume
Calculated Density
Cork
.15g
.3mL
.5g/mL
Marble
3.85g
1mL
3.85g/mL
Gold rod
8.6g
1mL
8.6g/mL
Copper rod
9.05g
1mL
9.05g/mL
White rod
1.15g
1mL
1.15g/mL
Matte gray rod
1.5g
1mL
1.5g/mL
Matte silver