Overview:
For this experiment, students are going to make salt crystals by only using water, salt, string, pencil and a cup. When heated water and salt are combined the water will then grab on to the string. Then the water will evaporate and the salt will stay behind so it can start to create a crystal
Time:
24-48 hours
Lesson Materials:
*You can use the document in the link below to either: tailor the experiment to your needs or to have a printable version of this lesson plan*
The plan is editable and printable. Copy the Google Doc in your own drive and make edits or you can just print.
Salt Crystals Lesson Video
Learning Objectives:
- Understand the basics between a liquid and how it can react.
- Test the experiment by using instructed materials.
- Analyze the experiment.
- be able to observe two important chemicals salt and water that form into a salt crystal.
Materials Needed:
- Pipe cleaner/string
- Pencil
- Cup
- Salt (4 scoops)
- Water
- Food coloring (optional)
Experimental Methods:
- Find a workspace that can get messy.
- Heat up a pan with 1 cup of water inside.
- Pour in ¼ cup of salt and stir until the salt fully dissolves. The water should look clear. Pour the hot water-salt mixture into a clean jar.
- Tie a string or a pipe cleaner around the pencil or popsicle stick
- The pipe cleaner or string should just dangle in the water. It should not touch the bottom of the jar. Cut the string or pipe cleaner to the correct size to dangle in the water.
- After its cut, balance the pencil on top of the glass jar so the string should be able to dangel inside the jar.
- Last move the jar to a safe place. It will take about 2 day to form crystals.
Variations:
- Try making multiple jars of solution. Place the solutions in a cool or hot environment. Does the crystal growth vary in different environmental conditions?
Questions to Think About:
- Can Salt crystals dissolve easily?
- Do Salt crystals take time to develop?
- What happens if you put too much Salt
- What happens if you pour less Salt and more hot water?
- Does it matter what type of salt you use?
- Can Salt crystals last for a long time?
- How is this related to society?
- Can it be helpful for something?
- Are crystals hard or soft after 2 days?
- Does food coloring make it better?
Chemistry:
Salt crystals are formed when hot water evaporates from a mixture of salt. There are many shapes for salt crystals. However hot water holds more than cold water. That’s because heated water molecules move farther apart, making room for more of the salt crystals to dissolve. When no more of the solution can be dissolved, you have reached saturation. As this solution cools, the water molecules move closer together again. Then crystals begin to form and build.
Society:
Salt crystals are related to society because it’s a way to enjoy a new experiment with salt and water. Kids see salt crystals everywhere. For example beaches, parks, mountains etc. I believe kids should care about all of this because it is a way to learn new things with materials around the house. It can also be an activity which can bring the community together and have fun.
Logistics:
STEAM Subjects: Chemistry
Science Vocabulary:
Supersaturated solution, chemical reaction, experiment
References:
US, Bayer. “Salt Crystals Experiment.” Medium, 29 Dec. 2017, thebeakerlife.com/salt-crystals-experiment-bdcb9f7f1d3. https://thebeakerlife.com/salt-crystals-experiment-bdcb9f7f1d3
Blog: https://www.childrensmuseum.org/blog/real-science-borax-crystals
Real Science: Borax Crystals | The Children’s Museum of Indianapolis. November
