Advertisements
Advertisements
प्रश्न
Distinguish physical and chemical changes.
Advertisements
उत्तर
1. Physical changes:
- No new substance is formed
- Reversible
- Change in physical properties like size, shape, state
- Melting of ice, tearing of paper freezing, evaporation vaporization
2. Chemical changes:
- New substance is formed
- Irreversible
- Change in properties of reactants and products
- Burning of paper, photosynthesis, digestion of food, rusting of iron
APPEARS IN
संबंधित प्रश्न
Classify the following as chemical or physical change:
Rusting of almirah
Classify the following as chemical or physical change:
Passing of electric current through water, and water breaking down into hydrogen and oxygen gases.
Classify the changes involved in the following process as physical or chemical changes:
Photosynthesis
Write short answer.
Give two examples of periodic changes
State whether the following is physical or chemical changes.
photosynthesis —
Tick (√) the correct alternative from the choice given for the following statement.
A substance which can not sublime is
State which of the following pertain to – chemical changes.
- Substance retains its identity.
- The change is permanent.
- No new substance is formed.
- Is easily reversible.
- Produces one or more new substances by a change in its composition.
- The change is temporary.
- The composition and properties of the original substance are not altered.
Give four reasons why the burning of a magnesium ribbon in the air is considered a chemical change.
State which of the following 1 to 5 pertain to – A: Physical Change B: Chemical change :
- Sublimation.
- Fermentation.
- Liquefaction or condensation.
- Magnetization.
- Respiration.
Higher order Thinking question
Boiling of water is a physical change; but boiling of egg is a chemical change. Why?
