10 Science Experiments Using Salt for Home and School

Salt is a brilliant, versatile and inexpensive ingredient for science at home. It can be used to cool a drink or make ice cream quickly, for a lava lamp, and to make coloured salt crystals. Salt is an interesting substance as it lowers the freezing point of water, leading to lots of exciting science experiments!

Salt can also be used to preserve food and is thought to have been used by humans since 6050 BC*.

Fun Facts about Salt

The salt we eat has the chemical formula NaCl ( sodium chloride ).

A mixture of salt and water can conduct electricity.

Salt can preserve food as it slows the growth of microorganisms.

Salt is used to treat roads in winter as it lowers the temperature at which water freezes.

Science Experiments For Kids Using Salt

Lift a piece of string with ice and salt

Use salt to lift a piece of ice with string. In this clever trick, the salt melts the ice around the string. The ice then refreezes over the string, allowing the ice cube to be lifted.

lift ice with string and salt science activity

Cool a drink with ice and salt

Find out how to cool a drink with ice and salt. This is a great activity for a sunny day and a fantastic visual science demonstration as you can watch the temperature drop in seconds.

a thermometer in a bowl of ice and water with a can of drink for a science investigation

Salt Lava Lamp

A salt lava lamp is a fun twist on the more traditional lava lamp activity. It’s easy to set up and looks great.

Coloured Salt Crystals

Creating coloured salt crystals is a brilliant way to learn about evaporation. You’ll need a warm day, food colouring, water and salt.

coloured salt from an evaporation investigation

Separate salt and pepper with static electricity

Did you know you can use static electricity to separate salt and pepper? Both salt and pepper are attracted to a charged object, but pepper is lighter, and so jumps up more easily.

Ballon covered in pepper from a separating salt and pepper science activity

Ice cream in a bag

Salt and ice are used to make ice cream in a bag. This traditional science activity tastes amazing and uses only basic ingredients. We like to use chocolate milk to make chocolate ice cream!

Salt and water density trick

Another simple science experiment using salt is this density trick. If you add salt to water, its density increases. This means you can create a colourful density demonstration with a layer of salt and water and a layer of food colouring and water.