DENSITY OF TWO METALS LAB

Name______

Date______Period__

Background Density is a physical property which can be used to identify substances. Density is calculated by dividing the mass of an object by its volume. The volume of an object can be measured two ways, by physically measuring the dimensions of a regularly shaped object and calculating its volume or by determining the volume by water displacement.

Purpose: To find the densities of two different metals.

Hypothesis: -Predict which metal will be more dense and identify a metal based on its density.

Procedure: 1. Fill a 25 mL graduated cylinder about half-way with water. 2. Place the graduated cylinder on a flat surface and read and record the amount of water to the nearest tenth. 3. Place the graduated cylinder with the water on the balance, read and record the mass. 4. Carefully SLIDE your entire sample of Metal A into the graduated cylinder. 5. Read and record the new mass and volume. 6. Repeat two times for Metal A (for a total of three trials). 7. Empty the water from the cylinder into a 400mL beaker. Do not pour into the sink! Dry the metal before returning it to the film can. 8. Repeat steps 1-7 for Metal B. 9. Record your data in your Lab Book on Data Table I: Metal A & Metal B. 10. Add your data (Averages only!) to the class results on the front board or the overhead transparency. This is Data Table II: Class Data- Metals A & B. Data Table: Copy and complete the following data table in your Lab Notebook. Start on a new page. It should cover the entire page. Data Table I: Metal A & Metal B

Volume Mass of Mass of Volume Mass Volume Density of Water Cylinder Cylinder of Water of of of In & Water Water & & Metal Metal Metal Metal Cylinder (Before) Metal METAL A TRIALS 1 2 3 AVERAGE ------

METAL B TRIALS 1 2 3 AVERAGE ------

Calculations & Graph

1. Calculate the mass, volume, and density of Metal A and of Metal B. 2. Graph the compiled class data on one set of axes. 3. Find the slope of each line on the graph - Metal A and Metal B. 4. Write the slope on the graph.

Analysis Questions:

1. Compare the slope to the densities you calculated. 2. Use the chart below to help you identify Metal A and Metal B.

Metal Density

g/mL

Lithium 0.53

Aluminum 2.7

Zinc 7.1

Copper 8.9

Lead 11.3

Gold 19.3

Tin 7.3

In your Lab book write: Metal A is ______Metal B is______

Data Table II Class Data (Averages)-Metals A & B Station/Group METAL A METAL B Mass Volume Mass Volume 1 2 3 4 5 6 7 8 9 10 11 12 13