Practicing Laboratory Techniques: VOLUME

b. VOLUME : The amount of Space in an object

This is an additional procedure for LAB 3 :

(Requires Two Days)

PART ONE

1. EACH Person : Label a Reaction tube "A".

2. Measure exactly 0.5 mL of blue solution using a volumetric pipette. Empty the .05 mL directly into the Reaction tube labeled "A"( Be able to identify this tool.) Label it with a number for each person in the group, A1, A2, A3, A4.

3. Measure exactly 0.5 mL of yellow solution using a pipette. Empty the 0.5 mL DIRECTLY into the reaction tube "A"

SHOW this solution to Mr. Ulmer for a signature on your lab paper: Write "Volume : Pipette _____________"

4. Put this aside for use in part three. Be sure to put a group identifier on the tube...Use a letter or initials, or symbol; because the tubes will be collected in a class-wide rack overnight.

PART TWO

1. Obtain a sample of colored blocks. Record the number of blocks : _____________.

2. Take the mass of the blocks and record it : _______________________.

3. Find the volume of the blocks by measuring with a ruler ( in cm) and calculating : L x W x H : __________________________.

4. Calculate and record the density of the blocks. D= M/V , Show the set up , units, and formula: ______________

PART 3: INQUIRY : Using a Centrifuge

1. Work in your lab group. Get a 20 mL sample of milk solution. This is approximate, so you may use a beaker. Get a disposable plastic pipette. Each person must pipette 1 milliliter of the milk solution into a reaction tube. Label your tubes, A5, A6, A7, A8 representing each person's work.

Identify who is A5, etc on the lab report.

2. The tubes must be balanced in the centrifuge. They are place across from one another in the centrifuge.

Add the Reaction tubes , "A" from part one and spin them. You are spinning all of the samples, the milk and solution A from part one.

3. Close the lid of the centrifuge completely . Turn it on, to spin the samples.

4. Spin the samples for three minutes.

5. Remove the samples and place them into a test tube rack. Do not disturb the solutions before observing them. Do not tip them, hold them upright.

6. Write an observation about what has occurred. You may take a picture of the tubes with your phone or Chromebook. You can print the photo as part of your lab report.

7. Inquiry Research : Why has this occurred?

8. Samples may be disposed of in the sink. The tubes go in the trash. Save the pipette.