Here are the experiments the kids did at our backyard science playgroup.
Science Playgroup – Chemistry
Make a Volcano
2 T baking soda
4 drops of food coloring
½ T (approx.) dish soap
¼ C vinegar
Place baking soda in the bottom of the cup. Top with food coloring and dish soap. When ready, pour on vinegar and watch the fun! Point out how the baking soda & vinegar caused a chemical reaction that makes the two liquids turn into a gas (the soap is just for added effect.)
Oobleck
1/3 C Water
5 drops of food coloring
¾ C Cornstarch
Mix together water & food coloring in a dish. Slowly add cornstarch to water mixture. Do not stir! Let mixture stand for 2 minutes. Then pick up and play with it. Add a couple more drops if the mixtures doesn’t turn from a solid into a liquid. Point out that this can be both a solid & a liquid. Tell them that corn is a polymer and polymers make it hard for liquids to move, so it acts like a solid until it is able to move and act like a liquid again.
Slime
¼ C Starch
3 drops food coloring
¼ C White Glue
In a plastic bag, pour in starch, put in drops of food coloring and squeeze to make starch colored. Next pour in white glue. Seal bag and begin squeezing the 2 ingredients together. When it makes a solid, you can take out slime and pour out excess liquid (which should be minimal). Have fun playing with your stretchy slime. Point out how when these 2 liquids are mixed together they form a solid.
Water Soluble Packing Peanuts
Tell them how water soluble means it can be dissolved in water. Demonstrate.
Melting Ice Experiment
1 tray of ice cubes (left as is)
1 tray of crushed ice
1 tray of ice cubes
1 solid tray of ice
Leave one tray of cubes as it is. Sprinkle salt on top of the other 3 kinds of ice. Tell how salt lowers the melting point of ice, so it makes it melt faster. Watch to see if different sizes of ice melt more quickly than other or in different ways when ice is applied.
Sun Prints
1 piece of construction paper
various items that will lay flat on paper
Lay items on top of contruction paper (darker colors work best) for 1-4 hours. Remove items and see the prints left behind. Talk about how the UV rays from the sun cause a chemical reaction in which the dye in the paper breaks down and causes it to fade in the spots that were not colored.
