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Question
Using the knowledge of acids and bases, write a secret message with the help of baking soda and beet root. Explain how it works.
(Hint: Prepare baking soda solution in water. Use this solution to write the message on a sheet of white paper with a cotton bud. Rub a slice of fresh beetroot over the message.)
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Solution
To write a secret message using baking soda and beetroot:
- Prepare the solution: Dissolve baking soda in water to make a solution.
- Write the message: Use a cotton bud dipped in the baking soda solution to write a message on a sheet of white paper. Let it dry completely.
- Reveal the message: Rub a slice of fresh beetroot over the dried message.
Explanation:
Baking soda is a base, and beetroot contains a natural pH indicator. When the beetroot juice comes into contact with the baking soda, it changes colour, revealing the hidden message.
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