Tag: classification of changes
Questions Related to classification of changes
All chemical reactions are :
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reversible
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irreversible
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exothermic
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endothermic
A change in which one or more than one new substances are formed is known as a chemical change.
Sheet erosion is due to _________.
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fast running rivers
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heavy rains
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occasional rains
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wind
Sheet erosion is the detachment of soil particles by raindrop impact and their removal downslope by water flowing overland as a sheet instead of in a definite channel.
Which of the following changes are irreversible?
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Milk to paneer
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Cow dung to biogas
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Grain to its flour
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All of the above
All of the following changes are irreversible because we can not convert the product into reactant again.
1) Milk to paneer.
2) Cow dung to biogas.
3) Grain to its flour.
Iron adopts changes slowly and gradually by process of :
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rusting
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moldings
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fermentation
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explosions
Burnt sparklers and burnt books pages are examples of
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reversible change
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irreversible change
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no change
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none of the above
Burnt sparklers and burnt books pages are examples of irreversible changes, as they are permanent changes which cannot be undone. Once these materials are burnt in to ashes, the original materials cannot be recovered back.
Which of the following is not a reversible change?
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Heating of water to steam
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Cooking of egg to scrambled eggs
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Heating of wax to molten wax
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Cooling a cake
Which of the following change cannot be reversed ?
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Hardening of cement
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Freezing of ice cream
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Opening a door
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Melting of choclate
Burnt sparklers and burnt books pages are examples of:
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reversible process
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irreversible process
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rusting
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none of these
Irreversible changes $-$ because when they are burnt formation of gas and ashes takes place i.e. chemical reaction is taking place and new substance are formed which can't be reversed back.
Which of the following changes are irreversible?
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Raw egg to boiled egg
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Woollen yarn to knitted sweater
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Bud to flower
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All of the above
The following changes are irreversible.We cant covert product into reactant in these processes
3) Bud to flower.
Which of the following represents a reversible change?
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A metal rod on heating expands (its length increases).
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A metal rod on cooling contracts (its length decreases).
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Both of the above
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None of the above
The following represents a reversible change. A metal rod on heating expands (its length increases). A metal rod on cooling contracts (its length decreases).