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प्रश्न
Explain the following statement: Digestion is a chemical change.
उत्तर
- When we eat, our mouth physically break down food into small pieces.
- Mechanical digestion occurs in the mouth, stomach and small intestine.
- Food is chemically changed in digestion when new, smaller substances are formed.
- Moreover, we will never be able to get back the raw material in the same form as it was before.
- Digestion of food is a permanent change which is irreversible.
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संबंधित प्रश्न
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heat.
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Name: A greenish-yellow gas.
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Classify each of the following, as a physical or a chemical change. Give reasons.
(a) Drying of a shirt in the sun.
(b) Rising of hot air over a radiator.
(c) Burning of kerosene in a lantern.
(d) Change the colour of black tea by adding lemon juice to it.
(e) Churning of milk cream to get butter.
Write the chemical reaction of baking soda with lemon.
