Chapter 8: Density mass volume density = for example, the density of benzene is: 0.880 g mL

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Chapter 8: Density

massvolume

density =

for example, the density of benzene is:

0.880 g mL

Chapter 8: Density

0.997 g/mL

1.59 g/mL

13.5 g/mL

Chapter 8: Density

0.880 g mL

What is the mass of 25.0 mL of benzene at 20°C? (Density = 0.880 g/mL)

X 25.0 mL = 22.0 g

Chapter 8: DensityLab activity: Pipetting different density sucrose solutions

Insert pipette by holding it near the end closest to the pipetter

Don’t hold the pipette at the other end! It could break and stab your hand!

Chapter 8: DensityLab activity: Pipetting different density sucrose solutions

push here to bring liquid up ( ) the pipette

push here to move liquid down ( ) the pipette

practice pipetting with a beaker of water

Chapter 8: DensityLab activity: Pipetting different density sucrose solutions

make sure you read the correct scale!

9 mL

10 mL

Chapter 8: Density

1. Line up four glasses. Add 15 g of sugar to the first glass, 30 g of sugar to the second glass, 45 g to the third glass, and 60 g to the fourth glass.

2. Add 45 ml of water to each of the glasses. Stir each solution. If the sugar does not dissolve in any of the four glasses, then add one more tablespoon (15 ml) of water to the glass.

3. Add 2-3 drops of red food coloring to the first glass, yellow food coloring to the second glass, green food coloring to the third glass, and blue food coloring to the fourth glass. Stir each solution and record the volume.

Chapter 8: Density

4. Now let's make a rainbow using the different density solutions. Fill a 15 mL Falcon tube with 2 ml of the blue sugar solution.

5. Carefully layer 2 ml of green sugar solution above the blue liquid. Do this by slightly tilting the Falcon tube and pour the green sugar solution down the side of the tube. If you do this right, you won't disturb the blue solution much at all.

6. Now layer 2 ml of the yellow solution above the green liquid, using the same technique. Finally, layer 2 ml of the red solution above the yellow liquid.

Chapter 8: Densitynow calculate the densities!

? g/ml sucrose

? g/ml sucrose

? g/ml sucrose

? g/ml sucrose