Chalk it Up

Purpose: The purpose of this activity is to determine the number of the formula units of CaCO₃ (chalk) that are deposited onto a chalk board.

Procedure:

Carefully record the mass of a piece of chalk.
Write your name of the chalkboard.
Reweigh the chalk.

Data: Create your own data table here.

Data Analysis:

Show a word formula and sample calculation:

Calculation the mass of chalk deposited onto the board.
Convert grams of chalk CaCO₃, to formula units.

Compile your data with that of 9 other classmates. Input into List 1 (L1) of the graphing calculator. Go to stat. Arrow over to calc. Select one variable. Select enter. Find the following:

The mean () with the standard deviation (S_x)
The range with minimums and maximums
The median

Discussion:

What is chalk made of?
How does it form?
Why is there so much limestone in Florida?
Why can you pick up a piece of white limestone off the ground and write your name with it on a sidewalk?
How many formula units of CaCO₃ are in one mole of CaCO₃?
How much does one mole of CaCO₃ weigh?
How many times would you have to write your name to use up 0.50 grams of chalk?