Hooked on Science: Rock testing

Using a common household item, you can determine what type of rocks are in your backyard.

Materials

* Vinegar

* Various rocks

Instructions

STEP 1: Pour the vinegar over each rock.

Explanation

If bubbles appear when placing the vinegar on the rock, the rock contains a large amount of calcium. Limestone is a common sedimentary rock that contains calcium. The vinegar reacts with the calcium, creating carbon dioxide bubbles.

Jason Lindsey is a Science Outreach Educator with Hooked on Science. Check out his website "Hooked On Science" at hookedonscience.org for webcasts and experiments that might get you hooked on science. Send him your science questions at jlindsey@hookedonscience.org. More science experiments can be found at www.semissourian.com.