Getting Messy With Science: A Science Experiment with Solutions

What is a solution?
A solution is a substance made up of solute and a solvent. A solute is a solid that will dissolve. A solvent is the liquid you dissolve it in, most commonly water.
Experiment
Materials:
Red or blue food coloring
2/3 c of tap water per jar/bowl
3 Mixing bowl or jars
3 Spoons
2 c cornstarch
1/2 c Sugar
1/2 c Salt
Getting Dirty
Put three drops of food coloring in each jar/bowl. Add 2/3c water to each. Stir.
Add the sugar to one jar.

Add the salt to another jar.

Shake both jars until you dissolve as much sugar and salt as you can.

Compare the two jars.


What has happened? Why does one jar have more solute left while the other is completely gone?

Now do the same with the cornstarch. Youʼll have to use a spoon to stir the mixture instead of shaking (if youʼve used a jar).


Is it harder to mix the cornstarch? Continue mixing the cornstarch but notice that something different is happening.

When the cornstarch and water begin to look a little bit solid youʼve reach the right point!


Reach in and take a handful of the mixture and form a ball by rolling it between your hands. Stop rolling and let the mixture sit in your palm.



Wow! What has happened? Is the substance a liquid or a solid? Itʼs actually neither!

What happens

While you are rolling the mixture between your hands, it feels dry. When you stop rolling, the ball suddenly turns to ooze!
Why it happens
What happens if you take water and stir sugar into it? What about the salt?
They both dissolve. They fill the empty spaces in between the water molecules, making a solution. When there are no more spaces to fill the water wonʼt hold any more sugar or salt and the solute (the sugar or salt) will collect at the bottom of the glass.
What happens if you take water and try to dissolve cornstarch into it?
The cornstarch will not form a solution, instead the cornstarch particles are simply held together by the water. This mixture is called a suspension. When you roll the mixture in your hands, it squeezes together on all sides and feels dry. But, when you stop rolling or applying pressure, the cornstarch particles in the mixture drift apart, creating ooze!
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When Michelle isnʼt getting her hands messy with science experiments she can be found blogging about her family at Pass The Flu Bug, Please.

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