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प्रश्न
Select the correct answer from the choice given below to complete the sentence
A change in which a substance retains its identity is a
______ change.
विकल्प
physical
chemical
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उत्तर
A change in which a substance retains its identity is a physical change.
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संबंधित प्रश्न
Tick the most appropriate answer.
5. Photosynthesis requires
- heat energy.
- wind energy
- sunlight.
- sound energy
Match the columns
| column A | coulmn B |
| 1. A change which cannot be easily reversed | a. man-made change |
| 2.A change that repeats itself at regular intervals | b. chemical change |
| 3. A change that is made by humans | c. physical change |
|
4. A change in which the original substance cannot be obtained |
d. periodic change |
| 5. A change where no new substance is formade | e. irreversible change |
| f. slow change |
Fill in the blank.
Growing of a seedling into a plant is _______ change.
State whether the following is physical or chemical changes.
mixing oil with water —
Given reason:
Burning of paper is a chemical change.
Explain the term – ‘sublimation’. Is sublimation of naphthalene – a physical or a chemical change. Give reasons.
State why addition of sodium chloride to water is considered a physical change, while addition of dilute sulphuric acid to zinc is considered a chemical change.
Compare the energy changes involved during a physical and a chemical change.
Give the reason why the following is considered as chemical changes.
A piece of magnesium strip is dropped into a beaker containing dilute hydrochloric acid.
Higher order Thinking question
Boiling of water is a physical change; but boiling of egg is a chemical change. Why?
