How Do Chemicals Weather Rocks?
Place an equal number of limestone or marble chips in each of two jars. Cover the stones in one jar with water and those in the other with vinegar; then screw lids on the jars. Allow the jars to stand overnight. You may notice some bubbles forming in the jar with the vinegar. Ask the students to speculate about what this might mean. The next day, pour out the liquid from each jar into separate bowls. Label the bowls “water” and “vinegar”. Allow the water in the bowls to evaporate. Compare the amount of solid material remaining in the two bowls. The bowl that contained vinegar will have a larger amount of solid material. (Limestone, marble, and other carbonate rocks react with acid to form carbon dioxide and soluble salts. Rainwater is often acid and can erode limestone easily. Acid groundwater dissolves limestone underground, forming caves and sinkholes. Study or visit any caves or sinkholes in your area. Examine other types of rock to see if they react to vinegar in the same way as ca