State whether the following statements are true or false:
(a) When a candle burns, both physical and chemical changes take place.
(b) Anaerobic bacteria digest animal waste and produce biogas.
(c) Ships suffer a lot of damage though they are painted.
(d) Stretching of rubber band is not a physical change.

Academic Chemistry NCERT Class 7

(a) True

(b) True

(c) True

(d) False

The stretching of a rubber band is a physical change.

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Updated on: 01-Feb-2023

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When a candle burns, both physical and chemical change take place. How?
When a candle burns, both physical and chemical changes take place. Identify these changes. Give another example of a familiar process in which both the chemical and physical changes take place.
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