To get a Do Science logo product, click here. Send a t-shirt with an activity on the back (Condiment Diver activity is on back). Return to The Archive List Do you have a comment or response to this activity, submit it to the Do Science bulletin board. More science activities can be found here: Great for Science Fair projects! While You're Waiting for the Food to Come by Eric Muller, Illustrated by Eldon Doty Hardcover version Paperback version To order or find out more about this book, click on the book cover above or on either cover version. Go to the Do Science Store

Make liquids drip-up and down. Create a homemade (restaurant-made) lava-lamp. Ingredients: -Salt -Salad oil (olive or sesame oil are best) -Tall clear glass of cold water, no ice The Recipe: 1) Fill a glass about 3/4 full with cold water. 2) Slowly pour some oil into the glass. Because oil is less dense than water, the oil will float. Stop pouring when you have a layer of oil about 1/2 inch or 1 cm thick on the water's surface. 3) Next, generously sprinkle salt on top of the oil and watch what happens. 4) Add more salt or any other condiment to see what else might happen. Food for Thought: Oil is less dense than water, so it floats. Salt is more dense than both water and oil so it sinks. What makes things interesting in this trick is that the oil tends to cling to the salt temporarily. Together, the oil and salt blobs are denser than water, so they descend to the bottom of the cup. As the blobs go down, the oil coats and protects the salt from dissolving. However, after it sinks, the oil soon yanks free from the salt and floats up again. Copyright 1996 Eric Muller While You're Waiting for the Food to Come" Original copyright of While You're Waiting for the Food to Come 1995 Eric Muller