Easy Science Experiment with Salt: Great for Science Fairs

We have a simple science experiment with salt that your kids will love and is a really cool (literally) simple science fair idea.  This salt experiment studies the freezing temperature of water and how salt affects it.  Kids Activities Blog love cool science magic tricks that make learning fun. Use our simple science projects at home or in the classroom.

Science Experiment with Salt – easy!

With this simple science project, we will explore the question, Can you lift an ice cube into the air using nothing but a piece of string? This frozen salt STEM experiment is sure to please whether you are exploring the curiosity of a preschooler or conducting a formal science experiment in the classroom.

Related: Egg Test & Cool Science Fair Project Ideas

To get more out of simple science, check out our scientific method for kids worksheets!

Supplies Needed for Science Experiment

• A glass filled with water
• An ice cube
• A piece of string
• Salt
• Scissors to cut the string to desired length

Instructions for Salt Science Experiment

Step 1

To conduct this simple science experiment, place the ice cube into the glass of water. The ice cube will float on top of the water.

Step 2

Next, take your length of string (it will work best if you use a wet piece of string) and lay it across the ice cube. Ask some questions:

• Can you pick up the ice cube?
• What could we use as “glue” to attach the string to the ice cube?

Step 3

Here’s how to make the magic happen. Place the wet string on top of the ice cube, sprinkle some salt over the ice cube and string and wait for one minute.

After one minute, lift the string by holding it at each end.

The Science Behind this Simple Experiment

Why can the string now attach? How can it life the cube out of water?

Salt lowers the freezing point of water so where the salt meets the ice cube, the ice melts quickly. It only takes a few seconds for the water to refreeze into ice and surround the string. When this water refreezes, the string is now stuck to the ice cube and can be used to lift it out of the water.

Salts Affect on Freezing Water

So salt lowers the freezing point of water. Can you think of a common every day scenario where this fact is useful? How about during winter snowfalls when roads and sidewalks are slippery and covered with ice? That’s why we sprinkle salt over these surfaces to melt the ice and make them safer.

Our Experience with this Experiment

This classic experiment with salt and ice was an absolute winner with my son. He is four years old and loves the “magic” of simple science experiments. This one requires only a few simple materials, takes just a couple of minutes to do, and produces a real “wow” factor.

More Science Fun from Kids Activities Blog

Did your kids love this simple salt and ice STEM experiment? Did you do any modifications? Tell us in the comments below!