Advertisements
Advertisements
प्रश्न
Give four reasons why the burning of a magnesium ribbon in the air is considered a chemical change.
Advertisements
उत्तर
BURNING OF MAGNESIUM RIBBON is chemical change as It is
- Irreversible change
- New product with new properties is formed (MgO)
- It is a permanent change
- Composition is changed
- Energy is required to bring the change.
APPEARS IN
संबंधित प्रश्न
Classify the changes involved in the following process as physical or chemical changes:
Photosynthesis
Define physical change. Give two examples for the above changes.
Write true or false
Earthquake is a desirable change.
Make a list of different types of changes with example.
Which of the following are chemical changes ?
- decaying of wood
- burning of wood
- sawing of wood
- hammering of nail into wood
Given reason:
Burning of paper is a chemical change.
Change is the law of nature which occurs in everyday life.
State when a substance [i.e. matter] undergoes a kind of change.
Compare the energy changes involved during a physical and a chemical change.
Potassium chloride is added to water and stirred. A salt solution is obtained, which is then boiled, leaving behind a residue.
- Is the above change physical or chemical?
- Name the residue which remains behind after the salt solution is boiled.
- Is the change reversible or not reversible?
- Are the composition and properties of the original substance altered?
- Give a reason why the above experimentation would not be possible if calcium carbonate was taken in place of potassium chloride.
Select the chemical changes from the following list of changes
Vaporisation of water into water vapour.
