Advertisements
Advertisements
प्रश्न
Two drops of dilute sulphuric acid were added to 1 g of copper sulphate powder and then small amount of hot water was added to dissolve it (step I). On cooling, beautiful blue coloured crystals got separated (step II). Step I and Step II are:
पर्याय
physical and chemical changes respectively.
chemical and physical changes respectively.
both physical changes.
both chemicals change.
Advertisements
उत्तर
both physical changes.
Explanation:
Dissolution of copper sulphate powder in water in presence of sulphuric acid is a physical change. On cooling this hot solution, the crystals of copper sulphate are separated. This is also a physical change.
APPEARS IN
संबंधित प्रश्न
Tick the most appropriate answer.
3. Physical changes are
- permanent.
- periodic,
- temporary
- irreversible.
Photosynthesis cannot take place at night.
Write short answer.
What are man-made changes ?
What is a chemical change ? Give two examples of chemical changes.
Give the main differences between physical changes and chemical changes.
Give a reason why
Change of seasons is a periodic change while the change of weather is a non-periodic 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
A change in which a substance retains its identity is a
______ change.
Distinguish physical and chemical changes.
When solute is dissolved in a solvent it forms a solution.
