The diagram below shows the appearance of two pieces of paper placed in different parts of a non-luminous flame of a Bunsen burner and removed...

The diagram below shows the appearance of two pieces of paper placed in different parts of a non-luminous flame of a Bunsen burner and removed quickly before they caught fire.

(a) What do the experiments show about the outer region of the flame?
(b) From the above experiment, which part of the flame is better to use for heating? Give a reason

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(a) It is very hot.
(b) The upper part. Because all the gases undergo complete combustion.

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sharon kalunda answered the question on March 29, 2019 at 13:32

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