Kitchen Chemistry - fun for all ages!
- Food Coloring + Soap: Pour some milk into a wide, shallow container. Put a few drops of food coloring on top. Dip a q-tip into soapy water and then touch it to the surface of the milk. The food coloring will be repelled by the soap!
- Ivory Soap + Microwave: Speaking of soap....put a bar of Ivory soap in the microwave for about 2 minutes. The air pockets in the soap will expand and it will grow into a big cloud of soap! It's hot at first but then fun to touch, compress, and sculpt. The soap can still be used - I grind it up and use it in my homemade laundry detergent!
- Red Cabbage pH Indicator: You can make a natural acid/base indicator using red cabbage! Chop and boil the cabbage in water until it becomes pale and the water becomes purple. Collect the purple water and combine small amounts of it with household items to determine if they are acidic or basic. Acids will turn the water pink; bases will turn it green. Things to test - cleaning products, lemon juice, jet dry, ground-up aspirin, soap. It's fun to see the colors change!
- Oobleck: A classic for any age! Just combine water and cornstarch in a wide, shallow container and play with it! It is a non-Newtonian fluid because it doesn't follow general physics principals. It is a liquid but exhibits some properties of a solid when under pressure.
- Coffee Filter Chromatography: Use water-soluble markers to make large dots on a coffee filter (use black, brown, and secondary colors). Place the filter into some water and the ink will separate into the colors it is composed of. There are lots of methods for this....but here is how I do it: Cut out a 1-cm round hole at the center of the coffee filter. Draw a pattern of dots near the middle half of the filter. Place a "wick" in the center hole (a rolled-up piece of another filter) and place the wick into a small glass of water. The decorated coffee filter can balance on top of the glass and the wick will use capillary action to absorb the water up from the glass and transfer it to the decorated filter. The ink colors will separate because the dyes have different molecule sizes and speeds so they do not all travel the same distance with the water. Using this set-up allows you to watch the inks separate (black and brown are the best!) and the whole thing takes less than 10 minutes.
- Shrinky Dinks: Use permanent markers to make designs on #6 plastic (most disposable cups and salad bar containers -- white and clear work best!). Heat the plastic in a 350 degree oven for about 2 minutes -- you can watch the items shrink! A cup shrinks down to a thick, flat disk. Use this method to make customized and sturdy plastic ornaments, luggage tags, and more!