You can find it in blood, sweat and tears. Salt – there is no life without it. It makes every cell in your body tick. It is Nature’s gift to all living things. Greek philosopher Plato called it a substance dear to the Gods.
Homer, the Greek poet referred to it as the ‘divine substance’. It aids intellectual growth. The list is endless. A project on salt is so easy to execute that it doesn’t really need a classroom. You could be on the beach or in the kitchen, it will be fun to do and full of activities and investigating opportunities. You will be surprised how many lessons can be generated from something as common place as salt.
The secret of tasty food: The easiest way to begin the project would be the food route. Ask your class to imagine the taste of popcorn or chips without salt or even their favourite curry. No doubt you’ll have every student making faces and weird expressions. You can explain to the class how taste buds carry the message to the brain to identify the taste of the food. Also discuss how the food tastes different when we are sick with cold. You may also discuss the myth about taste buds.
Now get children talking about the why salt is necessary in cooking. Explain how salt pulls out the water from the vegetables and hastens the cooking process.
Ask the students about their sea side holidays. Ask them to relive their experience; can they describe the scent of the sea breeze and the taste of the ocean?
Now that you have got them curious, get into deeper science concepts. While students of high school will learn about the chemistry of salt, the challenge is to get the younger ones interested with simple experiments to suit the age group.
Science experiments with salt
• Make a salt water battery
You will need
• 2 paper cups
• 2 zinc and 2 copper electrodes
• 3 small pieces of electrical wire
• 1 digital clock
• Table salt and water
- Attach one zinc and one copper electrode to the digital clock with wires. Join the other two electrodes with a wire to make a jumper. Fill the two cups with water. Dissolve salt in it. This will ionise the water.
- Now take the electrodes attached to the clock and place one each in the two cups of water.
- Now take the jumper and dip it into the water. Make sure that the zinc electrode of the jumper goes into the cup with the copper electrode and the copper one goes into the cup with the zinc electrode.
- Voila! The clock starts working and shows the time. You have generated current. Remove the jumper from the water and the clock stops.
- The two pairs of electrodes work to make the salt water battery and provide current to the digital clock.
- Take two glasses of water. Dissolve 2 tsps of salt in one. Place a few leaves of spinach in each glass for a day. Note the observations.
The author is a freelance writer based in Hyderabad. She can be reached at firstname.lastname@example.org.