Density Calculations

Let us start with a relatively simple calculation problem.

When a piece of aluminum was dropped into a graduate cylinder filled with 23.8 cubic centimeters of water, the volume reading changed to 26.3 cubic centimeters. What was the weight (in grams) of the piece of aluminum?

Before starting, consider what tools you will need to solve this problem. I will assume all of you have some paper, pencil, a standard calculator, and perhaps a periodic table that contains some element property data. If the latter is not available, we will open the Element Mode in the chemical calculator. (Alternatively, imagine you had assigned this problem to work out in class. How would you respond to each of the answers given by students?)

Locating Information in the Element Properties Database

To get started we need to locate the density of aluminum. One source of this information is in CHEMiCALC's Element Property database. When this mode is opened, you will see an empty element properties table, and a "small" periodic table.

ELMODE.gif

The "small" periodic table that displays only the representitive elements can be expanded to the full periodic table by clicking on the >> buttons.

FULLPT.gif

You can open up the element property database by clicking on the element symbol in the periodic table, or from the computer keyboard. (The latter, however, requires three keystrokes.)

1ALDENS.gif

Exploring Element Properties

Scroll down the database and highlight the density value of aluminum. Although not completely relevant to the present discussion, you may wish to explore graphically the periodic trends of this property. (A few examples.)

Exporting an Element Property

To continue the setup for the density calculation, we may export the density of aluminum and open up the Calculate Mode window by clicking on the 1TOCBTN.gif button.