Mrs. Kowalchik

Honors Chemistry II
Laboratory Experiment

Self-Directed Lab on Periodic Trends

Problem:

-  To graphically determine the density of germanium

-  To determine the relationship between density and position of any element in a group on the periodic table

Materials:

You may use any available glassware and balances. Small amounts of silicon (Si), tin (Sn), and lead (Pb) are available.

Procedure:

(This section should be completed prior to lab day)

1.  You and your partner are to design a lab procedure to find the densities of three metals in the same family of the periodic table: silicon (Si), tin (Sn), and lead (Pb). Write down the steps of your lab procedure in your laboratory notebook. Be specific!

2.  Prepare a table to record your data after your have written your procedure.

3.  Before you begin any lab work, be sure to show your procedure to myself. Your procedure must be approved in advance.

4.  After you have experimentally determined the densities of silicon, tin, and lead, prepare a graph that you can use to establish the density of germanium. The graph should be hand drawn in your lab notebook.

a.  To get you started, your graph should be titled Average Density vs. Atomic Number (remember titles are what is on your “y” versus what is on your “x”).

b.  Once points are plotted, draw a best-fit line and use interpolation to determine the density of germanium.

5.  Calculate the percent error of the density of germanium as compared to the accepted value (5.323 g/mL).

Constraints:

-  You must determine the density of germanium by using a graph based on your laboratory data.

-  You may NOT use published data or properties on your graph, in calculations, or in your determination of the density of germanium. This includes any textbooks or Internet sources.

Laboratory Considerations:

·  Consider how to obtain the most accurate data possible as you design your procedure

·  Read all lab equipment to the correct number of significant figures to be accurate throughout the lab

·  Use the correct number of significant figures when completing the calculations