Advertisements
Advertisements
Question
Sublimation is classified as a physical change. Why ?
Solution
Physical changes are those in which no new substance is formed. In sublimation there is direct conversion of solid into gas and vice versa. Thus the substance remains the same.
APPEARS IN
RELATED QUESTIONS
Classify the following as chemical or physical change:
Passing of electric current through water, and water breaking down into hydrogen and oxygen gases.
Solve this crossword by using the clues that follow.
Across
1. Energy in the form of sunlight is absorbed by the green plants in this process.
4. The reddish-brown substance formed over iron in the presence of oxygen and moisture.
5. This change is permanent and irreversible.
6. The process in which a solid directly changes into gaseous state.
Down
1. It is the change that takes place in case of swinging pendulum of a clock.
2. Occurrence of this is a non-periodic change as well as a natural change.
3. It is a physical change
Change is the law of nature and occurs in our everyday life, at all times and in all places. Differentiate between the following change with a suitable example.
Desirable and undesirable change.
Change is the law of nature and occurs in our everyday life, at all times and in all places.
Differentiate between the following change with a suitable example.
Periodic and non-periodic change
Differentiate between a physical change and a chemical change with reference to – Formation of products.
Fill in the blank with the appropriate word of the statement given below:
Germination of seeds is considered a __________ change.
State which of the following 1 to 5 pertain to – A: Physical Change B: Chemical change :
- Sublimation.
- Fermentation.
- Liquefaction or condensation.
- Magnetization.
- Respiration.
Assertion: Burning of wood log to charcoal is a physical change.
Reason: The products formed of burning a piece of wood can be easily converted back to wood log.
State whether the following statements are true or false:
Anaerobic bacteria digest animal waste and produce biogas.
Give two examples for each of the following cases:
Physical changes are reversible.