A few weeks before our vacation, the kids and I worked on the periodic table. We did this years ago, and Mavi was so excited to work on this activity again. This is a continuation of our Great Lessons, and if you are new to this post, you can revisit the first and second part of the activities here: (1) Experiments on the Laws of the Universe and (2) The Volcano
This experiment is perfect for the winter season! Make use of the snowy days by performing this simple experiment on why we put salt on icy roads during winter.
Objective:
To determine which substance or what condition will make the ice melt faster.
Mavi and I got the chance to work on some experiments last weekend due to bad weather. First we started off with a simple test of which substance dissolves in water.
Objectives:
Discovering which substance dissolves in water
Why the said substance dissolves faster in water
Materials needed:
salt, sugar, flour, chalk powder
4 bottles of water
teaspoon
stirrer
Procedure:
Findings:
Salt and sugar easily dissolved in water after stirring. They have grainy texture and are crystalline thus making it more soluble in water.
Flour and chalk powder partially dissolved, most of the powdered portion resided at the bottom of the bottles. They have powdery and dry texture, thus making it hard to dissolve in water.
FOR OLDER KIDS
Now, for older children who can grasp complex explanation… I prepared a visual and hands-on demonstration for Mavi to understand how the substance are more soluble, partially soluble and insoluble. Make sure though that when you try to discuss this with your kids, he/she is already familiar with the elements in the periodic table and can understand what “attraction” means, similar to the concept of magnetism. The link I provided is the one where I introduced the Periodic Table to Mavi in a fun and interesting way.
Anyway, here’s how the chemicals of the substance interact to water when mixed. SOLUBLE SUBSTANCE
I used plasticine to demonstrate the chemical composition of salt and water to Mavi. Salt is composed of: sodium (Na+) in green and chloride (Cl-) in purple. Water is made up of H2O, hydrogen (H+) in white and oxygen (O-) in red.
When mixed with water, the salt molecules are easily “attracted” to the water molecules. It’s like the positive and negative attraction in magnetism (polarity). Thus, sodium (Na+) is attracted to oxygen (O-), while chloride (Cl-) is heavily attracted to the two positively charged hydrogen (H+).
Because of the strong attraction between molecules in the two substances, salt is easily dissolved in water.
PARTIALLY SOLUBLE
For partially soluble substances, the molecules that made up the flour or chalk have weak attractions with the molecules of the water. Thus some have dissolved but most of it didn’t and the result are the residues found at the bottom of the bottles. INSOLUBLE SUBSTANCE
For insoluble substances (don’t dissolve in water) like oil, the molecular contents are NOT attracted to water. This means they do not mix with water and if you combine them, you will definitely see the separation.
Though some advanced students can explain that this is because oil is a non-polar substance and can only be dissolved with another non-polar substance, the way I explained it to Mavi is that oil molecules are just so heavy that water molecules can’t “bond” with it.
This was a fantastic activity for both Mavi and I. More experiments coming up! So follow us on Facebook, Pinterest, Google Plus, Instagram or Twitter for updates!
And you might as well PIN this for reference. Thank you!
This is Chemistry 101, and a lot of people have asked me if it is possible to teach kids all about the basics of elements to kids. I didn’t believe that until I came across this kid-friendly Periodic Table via social media.
