Children learn through discovery, exploration and play, which is why simple, at-home experiments are so effective in teaching youngsters scientific concepts. Use the hands-on, active learning that science experiments promote to foster a basic understanding of saturation -- that is, a solid’s or liquid’s ability to absorb and dissolve as much of another substance as possible. Always supervise experiments to ensure child safety, to provide thought-provoking questions for analysis and to answer any questions that fascinated, curious youngsters might have.
Basic Experiment for Young Children
All you need is a few clear glasses, tap water, a spoon and some salt to conduct a simple saturation experiment with youngsters. Fill one glass with cold tap water, and instruct your youngster to add the salt to the water, one teaspoon at a time, mixing after each teaspoon. The salt will disappear after you mix the first teaspoon in. After you have mixed a few teaspoons in, the water will stop absorbing the solute, which will sink to the bottom of the glass in a clump. The amount of teaspoons added just before the salt begins to settle at the bottom of the glass is the saturation limit. What happens when you add salt to a glass of warm water? Will it take more or less teaspoons to reach the saturation point of the warm water than it did the cold water? Encourage your child to determine the water’s saturation point for each glass using these guided questions to promote an understanding of saturation and cause-and-effect.
Experiments for Older Children
You can modify the same basic experiment for older children with a few additions and changes. Use a variety of solutes such as sugar, salt, baking soda, flour and sand, and encourage children to compare and contrast the different solutes, determining which water temperatures hold the most of which solutes, and which solutes dissolve easiest. Use other clear liquids, also. Will equal amounts of salt dissolve in the same amount of vegetable oil or white vinegar?
Edible Saturation Experiment
Homemade rock candy treats can double as a saturation experiment for kids, and all that’s needed is a few household items and some patience. Take a thick piece of cotton string, moisten one end with a little sugar water, and hang it to dry. Place one cup of water and three cups of sugar into a saucepan and carefully bring it to a boil, stirring constantly. This will allow the water to absorb all of the sugar, forming what is known as a super-saturated solution. Remove the saucepan from the stove top, add a little food dye, and then pour the solution into a glass jar. Take the string and wrap the clean end around a pencil, so that the sugared end dangles freely. Submerge the free end of the string into the jar, keeping it in place by laying the pencil across the jar. Place the jar somewhere where it can remain undisturbed, and in about two weeks, the rock candy will form.
Other Saturation Experiments
You can conduct saturation experiments with lots of household materials -- all you need is a little creativity and imagination. Take a tissue and instruct kids to add water to it with a dropper. How many drops of water will the tissue absorb before it begins to leak? Fill a measuring cup with water and then submerge a sponge in it. How much water can the sponge hold? For an experiment with an artistic twist, add colored water with a dropper to a piece of white construction paper. Use different colors to saturate the paper, resulting in abstract art with swirls and blotches of color.