Science in the Age of Covid Crisis Teaching - A simple experiment linking temperature to solubility.

Before we start: It is important to know that everything in the world is made up of atoms and molecules, which are tiny, tiny pieces of matter, so small that we can’t see them.

Background information:

Solutions (and mixtures)

diffuse: to spread out in every direction
solute: the substance that is going to be dissolved
solvent: the thing (in our case the liquid) that the solute is going to be mixed into in order for it to dissolve
dissolve: to mix a substance (solute) with a liquid (solvent) so that the molecules of the substance diffuse through-out the liquid

A mixture is when you combine (mix!) two or more things together. The type of mixture we’re looking at this week is called a solution. A solution is a mixture where all the bits of the two (or more) things we’re mixing together are so thoroughly combined (mixed) that you can’t easily separate them any more.

Today, we will be looking at dissolving honey into water. When we are working with creating this solution, we combine together the solute (the honey) and the solvent (water).

Our question: How does Temperature Affect Dissolving Rate?

We are going to test what happens when we try and dissolve honey in three temperatures of water: hot, lukewarm, and cold.  This will take some set up, and will require a little help from an adult.  

You will need:

- three clear glasses or glass jars, and one more for chilling the cold water
- some tape or scraps of paper for labeling your experiment
- measuring cups and measuring spoons
- a way to boil water
- 3 clean spoons
- 6 teaspoons of honey (if you don’t have honey, you can use golden or corn syrup... if you don’t have those you could use granulated sugar)
- 6 tablespoons of lemon or lime juice

Read through all the instructions. After you have read through all the instructions, think about what you know or what you have seen in the past with liquids, temperature, and mixing things together.  On a piece of paper, record your HYPOTHESIS (a hypothesis is a guess where you record what you think will happen and why).  Your hypothesis might look like this:  

The honey will dissolve fastest in __(hot/cold/lukewarm water)___ or
The warmer the water, the _(faster/slower)_ the honey will dissolve.

Instructions

1.) ONE HOUR BEFORE - fill a glass with one cup of water and put it in the fridge to get really cold
2.) MEASURE 2 tsp of honey (the solute) into each clear glass/glass jar.
3.) LABEL the glasses with the tape/scraps of paper - “boiling”, “room temperature”, “cold”
4.) PREPARE the solvents (the water). Boil some water, get the container of cold water from the fridge, and run the kitchen tap until you get the water to a temperature that is lukewarm/tepid (this means that it isn’t warm but isn’t cold either).
5.) POUR one cup of each temperature of solvent (water) into the glasses containing the solutes. (Get your adult to help you measure and pour the boiling water) DO NOT STIR (yet).
6.) OBSERVE the solutions. Which solvent dissolves the honey the fastest? Next? Last? You can test how well the solvent has dissolved the honey by using a (clean! don’t double dip, because we’re going to use the solutions for something else in a minute) spoon and getting a little bit of the solution out to taste it.
7.) STIR the solutions. How does that affect your experiment?
8.) RECORD your observations and check your hypothesis. Were you correct?

Report Out

In Science, it’s important that we report out our findings.  You will be handing in your findings to Mrs. Slack. She would like the following:

1.) Tell me what your hypothesis was.
2.) Tell me what you observed after you poured your solvents in the jar. What happened after you stirred the solutions?
3.) Why do you think the different temperatures changed how the honey dissolved?

Finally...

Usually, there’s an important rule in Science and it goes like this: Don’t Eat the Science. However, this is a special science experiment that is designed for you to be able to consume it. Add 2 tablespoons of lemon or lime juice to each glass. Stir, add ice if you want to get it nice and cold, and enjoy!