Advertisements
Advertisements
प्रश्न
What is a physical change ? Give two examples of physical changes.
Advertisements
उत्तर
Physical change: These are changes in which no new substances are formed. These are temporary changes, which are easily reversible. The substance, which is involved in a physical change, does not lose its identity.
Examples:
- Water, if boiled, can be cooled and condensed.
- Mixing of iron fillings with sand is a physical change because they can be separated by a magnet.
APPEARS IN
संबंधित प्रश्न
Make a list of different types of changes with example.
Tick (√) the correct alternative from the choice given for the following statement.
An example of both physical and chemical change is
Two chemical substances X and Y combine together to form a product P which contains both X and Y X + Y P
X and Y cannot be broken down into simpler substances by simple chemical reactions. Which of the following statements concerning X, Y and P are correct ?
- P is a compound
- X and Y are compounds
- X and Y are elements
- P has a fixed composition
Which of the following are physical changes ?
- melting of iron metal
- rusting of iron metal
- bending of an iron rod
- drawing a wire of iron metal
Photosynthesis is a natural process by which green plants manufacture food in the presence of sunlight.
State the conclusions which can be drawn, to represent photosynthesis as a physical or a chemical change.
Fill in the blank with the appropriate word of the statement given below:
If a change is permanent and irreversible it is considered a _________ change.
Distinguish physical and chemical changes.
Ice, water and water vapour look different and display different ______ properties but they are ______ the same.
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:
What kind of change is shown by tearing of paper?
