- A. position
- B. colour
- C. state
- D. composition
(c) State
(c) State
- A. Chemical change
- B. Undesirable change
- C. irreversible change
- D. physical change
(d) Physical change
(d) Physical change
- A. Chemical change
- B. Undesirable change
- C. irreversible change
- D. physical change
(d) physical change
(d) physical change
- A. rusting
- B. change of seasons
- C. earthquake
- D. flooding
(b) change of seasons
(b) change of seasons
- A. reversible change
- B. fast change
- C. natural change
- D. human made change
(d) human made change
(d) human made change
a reversible
an irreversible
undesirable
Natural
fast; slow
a reversible
an irreversible
undesirable
Natural
fast; slow
True
False – It is an irreversible change
False – It is a Natural change
False – It is a Chemical change
False – Water is the solvent
True
False – It is an irreversible change
False – It is a Natural change
False – It is a Chemical change
False – Water is the solvent
reversible
reversible
Natural
Natural
Irreversible
Irreversible
undesirable
undesirable
Fast
Fast
Reversible change
Reversible change
Blinking of eye (a fast change)
Blinking of eye (a fast change)
Curdling of milk (a chemical change)
Curdling of milk (a chemical change)
Trimming of hair (Man-made change)
Trimming of hair (Man-made change)
Burning of Kerosene (Chemical change)
Burning of Kerosene (Chemical change)
Decaying of plants is associated with slow change and chemical change.
Decaying of plants is associated with slow change and chemical change.
Yes, I can make a doll from the candle. The kind of change is a physical change.
Yes, I can make a doll from the candle. The kind of change is a physical change.
Changes which take place over a long period of time (hours/days/months/years) are known as slow changes.
Changes which take place over a long period of time (hours/days/months/years) are known as slow changes.
When Cane sugar is strongly heated, it will initially melt and after that start to decompose. It will turn brown and then black and give off fumes.
The changes involved are:
Physical change
irreversible change
When Cane sugar is strongly heated, it will initially melt and after that start to decompose. It will turn brown and then black and give off fumes.
The changes involved are:
Physical change
irreversible change
When the paper is burnt, oxygen from the air combines with carbon in the paper turning into carbon dioxide and water vapor which float away, leaving solid ash. The action of burning paper can’t be reversed. So, it is an irreversible change. Also, it is a Chemical change and a Fast change.
When the paper is burnt, oxygen from the air combines with carbon in the paper turning into carbon dioxide and water vapor which float away, leaving solid ash. The action of burning paper can’t be reversed. So, it is an irreversible change. Also, it is a Chemical change and a Fast change.
Deforestation cannot be considered a desirable change.
Because it is harmful to our environment and not desired by us are known as Undesirable changes.
Deforestation cannot be considered a desirable change.
Because it is harmful to our environment and not desired by us are known as Undesirable changes.
Germination of seed is a slow change.
Changes which take place over a long period of time (days) are known as Slow changes.
Germination of seed is a slow change.
Changes which take place over a long period of time (days) are known as Slow changes.
- A. Slow and fast change
- B. Reversible and irreversible change
- C. Physical and chemical change
- D. Natural and man-made change
Wax melts.
Candle keeps burning.
The size of the candle decreases.
The molten wax solidifies
Wax melts.
Candle keeps burning.
The size of the candle decreases.
The molten wax solidifies
When the candle is burning, the heat of the flame melts the solid wax to liquid wax. This signifies reversible (or) Physical changes. Also, as the wax melts, the size of candle decreases. If then molten wax solidifies and takes a different shape.
When the candle is burning, the heat of the flame melts the solid wax to liquid wax. This signifies reversible (or) Physical changes. Also, as the wax melts, the size of candle decreases. If then molten wax solidifies and takes a different shape.
- A. Melting
- B. Vaporisation
- C. Condensation
- D. Freezing
(d) freezing
(d) freezing
- A. Classification
- B. Composition
- C. Position
- D. Change
(d) Change
(d) Change
- A. Slow change
- B. Fast change
- C. Natural change
- D. Both (a) and (b)
(d) Both (a) and (b)
(d) Both (a) and (b)
- A. Physical
- B. Chemical
- C. Undesirable
- D. slow
(a) Physical
(a) Physical
Changes which can be reversed (to get back to the original state) are known as reversible changes.
Changes which can be reversed (to get back to the original state) are known as reversible changes.
Water is known as the universal solvent. It dissolves a wide range of substances.
Water is known as the universal solvent. It dissolves a wide range of substances.
