मराठी

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.

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प्रश्न

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.)

थोडक्यात उत्तर
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उत्तर

To write a secret message using baking soda and beetroot:

  1. Prepare the solution: Dissolve baking soda in water to make a solution.
  2. 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.
  3. 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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पाठ 4: Acids, Bases and Salts - Activities and Projects [पृष्ठ ४६]

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एनसीईआरटी Science [English] Class 7
पाठ 4 Acids, Bases and Salts
Activities and Projects | Q 1. | पृष्ठ ४६

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