Acid Rain's Effect on Marble

Author(s): Jim Schwagle, Kevin Bryan

Growth & Development Experiment 
SED 695B; Fall 2005

Research Question:

What effect does acid rain have on marble?

Standards addressed:

High School Chemistry

• 5d. Students know how to use the pH scale to characterize acid and base solutions.

• 5f. Students know how to calculate pH from Hydrogen ion concentration.

• 5g. Students know buffers stabilize pH in acid-base reactions.

Independent variable

Dependent variables

Controls

Series

Time

Change in mass of marble samples

Marble sample with application of distilled water

pH 4, 5, 6 and distilled water

Materials

Procedures

• 12 Marble samples

• Buffered solutions of pH 4, 5 and 6, 900 mL each

• 900 mL Distilled Water

• Analytic Balance

• 12-100mL Beakers

• 4-1000 mL containers for solutions

1. Obtain 12 marble samples of varying sizes, 1g to 5g, mass and record.

2. Separate samples into four groups of three. One each for use in the three pH solutions and one group for the distilled water.

3. Prepare 900mL each of the 4 solutions, pH 4, 5, 6 and distilled water.

4. Place 20mL of each solution into 12 containers.

5. Place each sample into the appropriate container, let sit for one hour.

6. Remove and dry. Discard used solution. Mass each sample at 5 day intervals and record.

7. Repeat immersion and drying each day for 15 days.

Blank Data table

Data table with starting masses, mass each week and % mass lost each week.

Click map for larger image at the source site

pH values for rain across the country.

This graph depicts the percentage of starting mass lost over time. Although distilled water seems to be missing, it is in fact underneath, and virtually identical to pH 6.

This statue has been slowly destroyed by acid rain so that now the faces are barely visible.

References & Links:

EPA Website

National Atmospheric Deposition Program Deposition Maps (Excellent maps of deposition of many different ions nationwide)