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Class 7
Science
Physical and Chemical Changes
explain why burning of wood and cutting it into sm...

Question:
Explain why burning of wood and cutting it into small pieces are considered as two different types of changes.

Answer:

Burning of wood and cutting it into small pieces are two different type of changes. When we burn wood, the new substance 'coal' is formed; it is a chemical change and this is not reversible. Whereas, cutting of wood into small pieces is considered as physical change because there is no formation of new substance occurs. Physical change means change in the physical properties of the substance. Here, cutting of wood into small pieces changes the size and the shape of the wood.

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Question:
Explain why burning of wood and cutting it into small pieces are considered as two different types of changes.

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Question: Explain why burning of wood and cutting it into small pieces are considered as two different types of changes.

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Question:
Explain why burning of wood and cutting it into small pieces are considered as two different types of changes.