Advertisements
Advertisements
प्रश्न
Name a chemical change which takes place in presence of:
Advertisements
उत्तर
Heat:
- Burning of paper.
- Cooking of food need heat.
Light :
- Formation of food by plants i.e. photosynthesis need light.
- Hydrogen and chlorine react in presence of light
Electricity:
- Water breaks into hydrogen and oxygen on passing electricity.
- Sodium chloride solution breaks up into its components sodium and Chlorine on passing electric current through sodium chloride solution.
APPEARS IN
संबंधित प्रश्न
Tick (√) the correct alternative from the choice given for the following statement
A pop sound is heard when a lighted match stick is brought near the mouth of a jar. This indicates the release of gas.
Write true or false
A natural change can also be a desirable change.
Which of the following are physical changes and which are chemical changes ?
Freezing of water
Which of the following are physical changes and which are chemical changes ?
Rusting of iron
Classify the following as a physical or a chemical change.
Manufacture of salt from sea water
Given reason:
Freezing of water to ice and evaporation of water are physical changes.
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
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.
Select the chemical changes from the following list of changes
Rotting of eggs.
Sublimation of Iodine is a ______.
