Advertisements
Advertisements
प्रश्न
What role does energy play in initiating a chemical change ?
Advertisements
उत्तर
In a chemical change molecules and atoms rearrange themselves to form new substances. This process involves some energy changes. In some changes energy is absorbed
e. g. burning of a substance and in some cases energy is evolved e.g. photosynthesis
APPEARS IN
संबंधित प्रश्न
What do you observe when :
a piece of paper is burnt
Fill in the blank
Burning of fuel is a _______ change.
State whether the following is physical or chemical changes.
passing electric current through a heater rod —
Give reason.
While purchasing canned food, its expiry date should be checked.
Give reason.
A dry handkerchief gets wet at once on dipping in water, but it takes longer for a wet handkerchief to dry.
Explain in brief the involvement of energy in physical and chemical changes.
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?
Paper, LPG, CNG petrol, etc, are ______ substances.
______ is the process in which something becomes different from what it was earlier.
Cut vegetables turn brown when exposed to air, this is due to ______.
