Advertisements
Advertisements
प्रश्न
Classify the changes involved in the following process as physical or chemical changes:
Photosynthesis
विकल्प
Physical change
Chemical change
Advertisements
उत्तर
Chemical change
APPEARS IN
संबंधित प्रश्न
Write true or false for the statement.
Dissolving of solute in a solvent and rusting of iron are both physical changes.
Ripening of fruits is a desirable change.
Match the columns.
| Column A | Column B |
| 1. a change which cannot be easily reversed | a. man-made change |
| 2 a change that repeats itself at regular intervals | b. chemical chang |
| 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 formed | e. irreversible change |
| f . slow change |
Write true or false
Burning of paper and formation of curd are reversible changes.
What is a physical change ? Give two examples of physical changes.
Fill in the blank.
The reaction in which energy is evolved is called
Fill in the blank with the correct word of the statement given below:
Sublimation involves a __________ 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 correct answer from the choice given below to complete the sentence
The dissolution of lead nitrate in water is deemed as a _________ change.
Give the reason why the following is considered as chemical changes.
A bright light is seen evolved when a strip of magnesium is heated.
