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प्रश्न
True or false?
In a chemical change, rearrangement of molecules and atoms involves some energy changes.
पर्याय
True
False
उत्तर
True
APPEARS IN
संबंधित प्रश्न
What do you observe when :
a piece of paper is burnt
What do you observe when :
solid ammonium chloride is heated
State whether the following is physical or chemical changes.
Melting of wax —
Tick (√) the correct alternative from the choice given for the following statement
When sugar is heated, its colour changes into
Melting of solid (wax) is a physical change.
What role does energy play in initiating a chemical change ?
Distinguish between the following.
Natural change and man-made change
Fill in the blank with the correct word of the statement given below:
Ammonium chloride, a sublimable solid undergoes _________ on heating.
Observe the picture containing a kettle and note that it has salt water in it and answer the following questions:
- What is name of the process that is done to the kettle?
- What will happen to the content of the kettle?
- What kind of change is occurring on the cold surface of the metal plate?
- What can you say about the quality of water that is obtained in the beaker?
Some changes are listed in the following table. For each change, write in the blank column, whether the change can be reversed or not.
| S. No. | Change | Can be reversed (Yes/No) |
| 1. | The sawing of a piece of wood | |
| 2. | The melting of ice candy | |
| 3. | Dissolving sugar in water | |
| 4. | The cooking of food | |
| 5. | The ripening of a mango | |
| 6. | Souring of milk |
