Chalk It Up to Science

Earth Science

By the Sea

Over time, water, wind and chemicals can wear down rocks. This wearing down of rocks is called erosion. Sand is made by erosion. It took millions of years to make all the sand on the beaches.

Main Activity

Materials

• chalk
• ruler
• vinegar
• activity log
• drinking glass
• pencil or pen

To Do

1. What do you think would happen if you left the chalk in vinegar overnight? Write down your guess on a sheet of paper.

2. Measure and record the length of the piece of chalk on your activity log. Be sure to record the date and time.

3. Fill the glass with about 1/2 cup of vinegar and place the chalk in the bottom of the glass.

4. Leave it overnight. Remove the chalk and measure its length again.

5. Observe and record what is happening to the chalk and the vinegar, as it dissolves.

Questions

Chalk is made of a whitish mineral called limestone. Why do you think the chalk wore down, or "eroded"? Can you find examples of the different types of erosion in your neighborhood?

Try This

Materials

• paper towel
• 2 rocks with rough edges

To Do

1. Lay the paper towel on a flat surface.

2. Scrape the rocks together over the paper towel.

Questions

What do you see on the paper towel? Does this material remind you of anything in nature?

Reprinted from Science in Seconds at the Beach by Jean Potter.

Feedback

Send the results of your activities, answers to these questions, or comments to tripod@miamisci.org.