The diagram below shows the heating curve of a pure substance. Study it and answer the questions that follow.

The diagram below shows the heating curve of a pure substance. Study it and answer the questions that follow.

(a) What are the physical states of the substances at points W and Y.
(b) Explain why the temperature remains constant between points B and C.

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(a) W – Solid
Y-Liquid

(b) The heat supplied is used to overcome intermolecular forces therefore causing the solid to melt.

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maurice.mutuku answered the question on September 19, 2019 at 08:33

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