Page 42 - Thola Issue 17

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thola: VOLUME 17. 2014/15
Ingredients
• Half a lemon
• Water
• Spoon
• Bowl
• Cotton bud
• White paper
• Ultraviolet (UV) light lamp or other
light bulb
Directions
1. Squeeze some lemon juice into the bowl and add a few drops of water.
K
D
S
INVISIBLE INK
2. Mix the water and lemon juice with the spoon.
3. Dip the cotton bud into the mixture and write a message onto the white paper.
4. Wait for the juice to dry so it becomes completely invisible.
5. When you are ready to read your secret message or show it to someone else, heat the paper by holding it close to a light bulb.
Conclusion
Lemon juice is an organic substance that oxidises and turns brown when heated. Diluting the lemon juice in water makes it very hard to notice when you apply it on the paper; no one will be aware of its presence until it is heated.
INFLATING A BALLOON
Ingredients
4. Once the balloon is fitted tightly
on the bottle opening, hold up the balloon and allow the baking soda to fall into the vinegar.
• Balloon
• Small bottle (cleaned plastic beverage
bottle)
• Small funnel
5. Observe the chemical reaction and effect on the balloon.
• 2 tsps baking soda
• 120ml vinegar
Directions
1. Using the funnel, add the baking soda to the inside of the balloon.
Explanation
2. Pour the vinegar into the bottle.
3. Carefully fit the balloon over the
This demonstrates the power of gas produced when baking soda and vinegar are mixed. The goal is for the balloon to be blown up by the gas created.
bottle opening, be careful not to drop the baking soda into the vinegar yet.