Today we will be doing a fun filtration experiment where salt goes through a filter like magic, while sand remains behind. This is one of the experiments in the book Christian Kids Explore Chemistry by Bright Ideas Press. The book provides a chart to fill in as we examine the salt and the sand at the beginning of the experiment.
You will need some sand, some salt, a funnel, a coffee filter, a mason jar or large drinking glass, a pie plate (without pie in it!), a glass measuring cup, a bowl, a teaspoon, and a stirring spoon.
Place 2 teaspoons of salt into the bowl. Add one teaspoon of sand to the salt, but don’t mix it yet. It helps to put salt on one side of the bowl and sand on the other side. Now you will want to taste the salt and the sand. You can spit out the sand when you are finished tasting it. You will have to watch the video at the end of this blog post to find out what my daughter said the sand tasted like.
Look at the salt and sand and feel it with your fingers. Which one is more coarse? Write that down on the chart. What color is the salt? What color is the sand? Are there any other characteristics your kids would like to mention about the salt or the sand?
Write down each of your findings on the chart provided in the book, and then doodle all over the rest of the paper as if you were a mad scientist. Just kidding. You don’t need to doodle.
Place the coffee filter into the funnel, and put the funnel on top of the mason jar. One child can hold the funnel while the other child pours the salt/sand/water mixture into the filter.
Where did the salt go? It disappeared!
Pour the contents of the mason jar into a pie plate, and leave it for a few days. When the water has evaporated, voila! The salt grains re-appear like a magic trick!
And the fun thing is that the salt crystals re-appeared larger than what they were at the beginning of the experiment!Tweet