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प्रश्न
While lighting a candle, Paheli observed the following changes.
- Wax was melting
- Candle was burning
- Size of the candle was reducing
- Melted wax was getting solidified.
Of the above, the changes that can be reversed are
पर्याय
(i) and (ii)
(ii) and (iii)
(iii) and (iv)
(i) and (iv)
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उत्तर
(i) and (iv)
Explanation:
Solid wax can be melted and melted wax gets solidifies again. Hence melting of wax and its solidification are reversible changes.
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संबंधित प्रश्न
Short Answer Type Question:
What is a chemical change? Explain with example.
Periodical removal of one of the products of a reversible reaction increases the yield.
A drawing sheet changes when you draw a picture on it. Can you reverse this change?
Water on ______ changes to ice and on ______ comes back to water.
Rolling of chapati and baking of chapati are the changes that ______.
A piece of iron is heated till it becomes red-hot. it then becomes soft and is beaten to a desired shape. What kind of changes are observed in this process-reversible or irreversible?
Give one example of change which occurs on cooling but can be reversed.
Give one example of change which occurs on mixing two substances, but cannot be reversed.
Paheli mixed flour and water and
- made a dough,
- rolled the dough to make a chapati,
- baked the chapati on a pan,
- dried the chapati and ground it in a grinder to make powder.
Identify the changes (i) to (iv) as the changes that can be reversed or that cannot be reversed.
Circle the odd one out. Give a reason for your choice.
