Lab 2- Percentage Error
Chemistry
Procedure:
Trial 1:
1) Measure out 0.003 L of water (You need to convert this into mL) into a
graduated cylinder. Write this down on your paper under volume of water.
2) Measure out 0.0088 lb of the white powder into a plastic container. (You will
have to convert this into grams). Write down your mass in your data table.
3) Pour your white powder into your graduated cylinder that contains water.
4) Determine the volume of the white powder. Put this in your data table.
5) What is the density of the white powder?
I know we have not talked about density yet….but the formula is easy.
Density = mass of white powder___
Volume of white powder
6) Write down your density in the data table.
Trial 2:
7) Measure out 0.005 L of water (Convert the volume into mL) into a graduated
cylinder. Put this on your paper for the volume of water.
8) Measure out 5.00 g of white powder and write your mass down in the data
table.
9) Repeat steps 3-6 above.
Trial 3:
10) Measure out 0.006 L of water (Convert the volume into mL) into a graduated
cylinder. Put this on your paper for the volume of water.
11) Measure out 0.013 lb of white powder (You will have to convert into grams
first) and write your mass down in the data table.
12) Repeat steps 3-6 above.
Data:
Volume of waterTrial 1- _____________
Trial 2- _____________
Trial 3- _____________
Trials
Mass of powder
Volume of powder
Density of powder
1
2
3
Post-Lab Questions:
1) Determine the average density of the white powder.
2) The actual density of the white powder is 1.59 g/mL. Determine the
percentage error of your measurements (average density).
Formula for percentage error
Percentage Error = Valueexperimental – Valueaccepted x 100
Valueaccepted
The accepted value is the actual value of substance.
The experimental value is the value that you found when doing the lab.
3) Was your average density for the white powder the actual density of the
powder? If not, what could have occurred during the lab process to cause
this?