Volume and Density Measurements Lab Report

I need an explanation for this Biology question to help me study.

 

 

Procedure

Part 1: Volume and Density Measurements (Liquid)

1. Gather the graduated cylinder, distilled water, short stem pipet, and isopropyl alcohol.
2. Place the clean, dry, 25 mL graduated cylinder on the tared scale. Record the mass of the graduated cylinder (g), in Data Table 4.
3. Fill the graduated cylinder with 5.0 mL of distilled water by using the short stem pipet to add water dropwise until the minuscus in the graduated cylinder reads 5.0 mL. Record the volume in Data Table 4.
4. Place the 25 mL graduated cylinder with 5.0 mL distilled water on the tared scale. Record the mass of the graduated cylinder and the liquid in Data Table 4 .
5. Calculate the mass of the water by subtracting “Mass A” from “Mass B.” Record the mass of the water in Data Table 4 .
6. Dispose of the water and fully dry the graduated cylinder.
7. Repeat steps 2–6 for isopropyl alcohol.
8. Calculate the densities of both the water and the isopropyl alcohol and record in Data Table 4 .

Note: The accepted value for the density of water is 1.00 g/mL and the accepted density for isopropyl alcohol is 0.786 g/mL.

1. Determine the percent error, using the equation below, between your calculated densities and the accepted values for both water and isopropyl alcohol.

 

$\text{Percent error(\%)}=\frac{\text{|experimental density – accepted density|}}{\text{accepted density}}\times \text{100\%}$

 

1. Record the percent error in Data Table 4.

Part 2: Volume and Density Measurements (Solid)

1. Gather the metal bolt, string, magnet, graduated cylinder, beaker, metric ruler, and scale.

Direct Measurement Method:

1. Tare the scale by pressing the Φ/T button so that the scale reads 0.0 g.
2. Place the magnet on the scale to measure the mass of the object. Record the mass in Data Table 5.
3. Use the ruler to measure the length, width, and height of the magnet in centimeters to the correct level of precision. Record the measurements in Data Table 5.
4. Calculate the volume of the magnet by multiplying the length by width by height, see equation below.

 

${\text{Volume (cm}}^3)=\text{length (cm)}\times \text{width (cm)}\times \text{height (cm)}$

 

1. Record the volume in Data Table 5.
2. Calculate the density of the magnet by dividing the mass by the volume, see equation below.

 

$\text{Density(}\frac{\text{g}}{{\text{cm}}^3})=\frac{\text{mass (g)}}{{\text{volume (cm}}^3}$

 

1. Record the density in Data Table 5.

Water Displacement Method:

1. Tare the scale by pressing the Φ/T button so that the scale reads 0.0 g.
2. Place the magnet on the scale to measure the mass of the object. Record the mass in Data Table 6.
3. Fill the graduated cylinder with between 6–8 mL of distilled water. Record the exact volume, to the correct decimal place, in Data Table 6.
4. Carefully slide the magnet into the graduated cylinder so that the water doesn’t splash, and read the volume of the graduated cylinder.
5. Record the volume in Data Table 6, next to “Final volume of graduated cylinder.”
6. Determine the volume of the object by calculating the difference in water displacement volumes (final – initial). Record in Data Table 6.
7. Calculate the density of the magnet and record in Data Table 6.
8. Carefully pour the water from the cylinder down the drain and collect the magnet.
9. Repeat steps 19–26 for the metal bolt.