Is It Possible to Lift the Ice Cube With a Rope Without a Knot?

 Overview 

Did you ever wonder why salt is used to de-ice roads? In this activity, you will use the same principles trying to pick up an ice cube with a string without a knot. Impossible, right? Materials in this experiment can easily be found in any kitchen.

Age: 5 +           Time: <20min

 Safety 

1. Contact with ice long may cause frostbite.
2. Be careful with the fragile glassware.

 Materials List 

• Small ice cube
• Cooking salt
• Cotton string

 Instruction 

Step 1/3 – Wet a cotton string and Place it on the ice cube.

Step 2/3 – Sprinkle a small amount of salt on the cotton string on the small ice cube and wait for 2-3 minutes.

Add caption

Step 3/3 – Lift the string and you can find the ice cube sticking to the string is lifted too.

 Troubleshooting 

What if I don't have a cotton string?
– Try other water-absorbing lines.

What if the ice cube falls when you are lifting it? 
– It is mostly because the cube is too heavy. In this case, the ice cube can be divided into some small parts.

What if the string does not connect to the cube? 
– It is mostly because too much salt is added or it is too soon to lift. The salt needs to cover just 1/2 to 2/3 part of where the ice and cotton string are connected. Or wait a longer time.

 Question to Ask 

1. How is the ice cube pulled up?
2. Can you pull it without salt?
3. Can you imagine how to use a rope to pull multiple ice cubes or multiple ropes to pull a large ice cube?

 Scientific Description 

The salt causes the freezing point of the water to decrease so it accelerates the ice melting process. When the ice turns to water, the rope absorbs water. The melting of the ice needs to absorb heat from the surrounding environment, so the temperature about is cool enough to freeze the water which is rich in a wet cotton string. Thereby, when the water freezes, the cotton string and the ice are sticking to each other so that the rope can lift the ice cube.

 Extensions 

1. You can add color, glitter into the water when you are making the ice cube. And, the ice cube will be colorful.
2. You can make the ice cube a fish or anything you like. Make it more appealing.
3. A rope can be used to connect many ice cubes at the same time. Many ropes to pull a big ice cube.

 Disposal 

The materials used are treated as domestic waste.