SCIENCE
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Change of shape
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Change of state
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Either A or B
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None of the above
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Detailed explanation-1: -A log can be cut down into small pieces to form kindling. During the formation of kindling, only the shape of the log is changing. Hence it is a change of shape (B).
Detailed explanation-2: -Cutting of wood into small pieces is a irreversible physical change as no new substance is formed and there is no change in chemical composition of wood. Whereas, burning of wood is a chemical change as a new substance is formed.
Detailed explanation-3: -physical change means changes are reversable and no new substances must be formed . chemial changes are irreversable and new substances are formed . so here cutting would give rise to wood piece in which no new substance is formed so its physical change.
Detailed explanation-4: -In a physical change there is no formation of a new substance. Chopping of vegetable is a physical change since only the size of vegetable is changing and there is no formation of a new substance.