Computer Applications
The diagram below shows the change of phases of a substance on a temperature-time graph on heating the substances at a constant rate.
(a) What do parts AB, BC, CD and DE represent?
(b) What is the melting point of the substance?
(c) What is the boiling point of the substance?
Calorimetry
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Answer
(a) The different parts represent the following:
- Part AB — It shows the rise in temperature of solid from 0°C to t1°C.
- Part BC — It shows melting at temperature t1°C.
- Part CD — It shows the rise in temperature of liquid from t1°C to t3°C.
- Part DE — It shows boiling at temperature t3°C
(b) The melting point of the substance is t1° C.
(c) The boiling point of the substance is t3° C.
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