Advertisements
Advertisements
प्रश्न
Classify the following as chemical or physical change:
Passing of electric current through water, and water breaking down into hydrogen and oxygen gases.
विकल्प
Chemical change
Physical change
Advertisements
उत्तर
Chemical change
Explanation:
The passage of electric energy through water to form hydrogen and oxygen gases is a chemical change because the properties of hydrogen (a combustible gas) and oxygen (a supporter of combustion) are completely different from those of water, which is neither combustible nor a supporter of combustion but does extinguish the fire.
APPEARS IN
संबंधित प्रश्न
Tick (√) the correct alternative from the choice given for the following statement.
A substance which can not sublime is
Write true or false
Deforestation is a man-made change.
Fill in the blank.
The reaction in which energy is evolved is called
Give four difference between physical and chemical 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.
Slow and fast change.
Explain the term – ‘sublimation’. Is sublimation of naphthalene – a physical or a chemical change. Give reasons.
Select the chemical changes from the following list of changes
Vaporisation of water into water vapour.
Give the reason why the following is considered as chemical changes.
Sulphur when burnt in air evolves a gaseous acidic product.
Classify the following changes as physical and chemical changes
A rough piece of wood is sanded and polished resulting in change in texture, Rusting of a iron nail, Painting the grill, Bending a paper clip, Pounding silver into thin plate, Rolling the chappathi dough into thin wire, Occurrence of day and night, eruption of volcano, burning of matchstick, dosa from the batter, blinking of eyelids, occurrence of a thunderstorm, rotation of the earth, formation of eclipses.
| Sr. No. | Physical changes | Chemical changes |
| 1. | ||
| 2. |
Mention some of the different conditions needed for chemical changes to occur.
