DiagramModerate3 marks
The melting point of naphthalene is 80°C and the room temperature is 30°C. A sample of liquid naphthalene at 100°C is cooled down to the room temperature. Draw a temperature time graph to represent this cooling. In the graph, mark the region which corresponds to the freezing process.
Topic: Heat and calorimetry
Previous-year question practice database
Answer
Solution diagram
Exam answer
Draw a cooling curve falling from 100°C to 80°C, remaining horizontal at 80°C during freezing, then falling from 80°C to 30°C.
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