Julie Franzak

ELED 305-42

6/7/2007

Science Area: Earth Science

Concept: Acid Rain

The Disappearing Statue

WOW #4

Materials:

Sticks of chalk

Vinegar

Water

Small plastic glasses (for each group)

Eyedroppers or straws (for each group)

Nails (for each group)

 

Procedures:

1. Explain: “Acids react chemically with limestone. Vinegar is an acid and chalk is a limestone.”

2. Fill a glass 1/3 full with water (for each group).

3. Place a piece of chalk into the glass filled with water.

4. Fill a glass 1/3 full with vinegar (for each group).

5. Either: Carve a statue out of chalk or shave off some of the chalk.

6. Place the statue in the glass filled with vinegar.

7. Drop single drops of vinegar onto your chalk using the eyedropper.

8. Observe the effects.

Questions:

1. Why did the lowest part of the chalk deteriorate more rapidly than the part of the chalk that single drops of vinegar were dropped on?

2. Why did this reaction to the statue occur in the vinegar and not the water?

Explanation:

Acid rain is comprised of more acid than normal rain; this develops through a complex process of chemical reactions involving air pollution. Nitrogen oxides and sulfur dioxide are the two most important pollutants that contribute to forming acid rain. When these two pollutants react with moisture in the atmosphere they form nitric and sulfuric acid. These sulfur and nitrogen compounds contributing to acid rain primarily come from man-made sources like industries and utilities and emissions that come from automobiles and other forms of transportation and other forms of industrial processes like melting.

Acid rain can harm forests, crops, damage bodies of water and contribute to the damage of statues and buildings. Acidic pollutants are deposited through the rain, snow, fog, dew and sleet; large quantities of acid rain can also be deposited in a dry form through dust. The pollutants that contribute to acid rain can be carried hundreds of miles before being deposited in the earth; this is one of the reasons why it is difficult to determine the specific sources of acid rain pollutants.

Source:

“Acid Rain: The Disappearing Statue”. http://www.reachoutmichigan.org/funexperiments/agesubject/lessons/other/statuel esson.html. obtained on June 1, 2007.