CECsci.208


TITLE:  "IT'S EATING AWAY AT YOU"

AUTHOR:  Judy Grunke, Weiser Middle School;
          Weiser, Idaho (borrowed from Falma Moye)

GRADE LEVEL:  K-8, Earth or Physical Science

TIME:  30 minutes--set-up, experiment, discussion.

OVERVIEW: Acid rain is a major pollutant in the world
today.  This activity is designed to show the effect of
acid rain on rock, edifices, and sculptures.

PURPOSE:  To show the effect of acid rain on limestone
rock.

OBJECTIVE(s):  The student will be able to:
1.   Demonstrate, using chalk and vinegar solution, the
     chemical reaction of acid on limestone.
2.   Explain what happens in this process.
3.   Identify the compounds used in the reaction and
     the gas which is given off.
4.   Tell where acid rain originates.
5.   Explain the effect of acid rain on limestone
     buildings and statuary.

RESOURCES/MATERIALS:
CLASS:  Textbook, acid rain
FOR EACH LAB GROUP:
     vinegar solution
     chalk
     eye dropper
     pan to set chalk in and to catch vinegar

ACTIVITY AND PROCEDURES:
1.   Place a piece of chalk in pan.
2.   Using an eyedropper, have one student drop vinegar
     onto the chalk in a constant stream.
3.   Observe the fizzing on the surface of the chalk
     when the vinegar is dropped.
4.   Notice the crumbling of the chalk.

TYING IT ALL TOGETHER:
1.   Students can research the causes (man-made and
     volcanic eruptions) of acid rain and efforts to
     protect valuable buildings and statues.
2.   Students can use the vinegar residue to
     demonstrate what happens to the dissolved material
     from chemical erosion by placing a small piece of
     basalt in the vinegar solution. (As vinegar
     evaporates, the dissolved material from the chalk
     precipitates to form a white mineral
     residue--caliche--on the surface.)